Lewin, Kurt

1890–1947

GERMAN/AMERICAN SOCIAL PSYCHOLOGIST, EDUCATOR, RESEARCHER

UNIVERSITY OF BERLIN, Ph.D., 1916

BRIEF OVERVIEW

At the time of Kurt Lewin's death in February 1947, he was widely regarded as one of the outstanding psychologists of his generation. Edward Tolman, the colleague who delivered a tribute to Lewin at a meeting of the American Psychological Association (APA) later that year, thought that Lewin could be compared to Freud himself.

Freud the clinician and Lewin the experimentalist—these are the two men whose names will stand before all others in the history of our psychological era. For it is their contrasting but complementary insights which first made psychology a science applicable to real human beings and to real human society.

One of many gifted scientists and teachers who fled Hitler's Germany for a new life in the United States, Lewin made significant contributions to so many different areas of psychology—child development, philosophy of science, psychology of prejudice, industrial psychology, organizational development, clinical psychology, personality structure, group process, leadership training, and others—that he has been called "the complete social scientist." As interested in applied psychology as he was in research, Lewin coined or popularized such terms and concepts as group dynamics, level of aspiration, sensitivity training, field theory, and action research. His colleagues also regretted that his sudden death had cut short the contribution he had hoped to make in the field that held together many of his other interests—the comparative study of science, or in Lewin's native German, vergleichende Wissenschaftslehre.

In spite of the range, depth, and originality of Lewin's work, however, he received less recognition during his lifetime than many psychologists whose work proved less durable. He was never elected to the presidency of a major scholarly or professional organization, was bypassed for major awards and honors, and was never offered a tenured professorship in one of the more prestigious universities. Much of his career in the United States was spent in such unlikely departments as home economics and child welfare. Nevertheless many of his theories and concepts became so influential that their origin was forgotten. His saying "There is nothing so practical as a good theory" is often quoted even in the early 2000s without recognition of its source. Lewin's personal modesty—he rarely added his name as coauthor to his students' published papers—and his ability to stimulate the creativity of his students and colleagues also meant that his innovations in experimental method as well as theory did not attract the attention they deserved.

Lewin's most lasting contribution to psychology may well have been his social conscience. His teaching of evening classes for blue-collar workers during his graduate school years in Berlin, his concern for equal education for women, his action research projects investigating anti-Semitism and racial prejudice—all of these inspired three generations of psychologists to undertake work that benefits the wider society as well as academic scholarship.

BIOGRAPHY

Childhood and early life

Kurt Lewin was born on September 9, 1890—what he himself called "the ninth nine of 90" in the small town of Mogilno, which is now part of Poland. At the time of Lewin's birth, however, it belonged to imperial Germany. His father, Leopold Lewin, ran a small general store on the ground floor of the family's home. The Lewins also owned a small farm a few miles outside Mogilno, where Kurt acquired a love of nature and enjoyed the freedom to explore the nearby fields and forests. He also had his own garden and became a skilled amateur mechanic.

Lewin's mother Recha was a warmhearted and energetic woman who reared her four children while she worked in the family store. Hertha, the firstborn child, was the only daughter. Kurt was the oldest of the three sons; his younger brothers were named Egon and Fritz. The family was close-knit and affectionate with one another. The Lewin family was not wealthy, but belonged to the financially secure middle class. Lewin's father served for a time as the president of the local synagogue.

In 1905, however, Lewin's family moved from Mogilno to Berlin because the parents wanted to give their children a better education than small-town schools could provide. Kurt was enrolled in the Kaiserin Augusta Gymnasium, a very selective high school that prepared students for university entrance. He was not regarded as an outstanding student until his last two years at the Gymnasium, when he began to study Greek philosophy and fell in love with it.

Lewin graduated from the Gymnasium in 1909 and entered the University of Freiburg, intending to study medicine and become a country doctor. He disliked the anatomy courses, however, and left Freiburg after one semester, transferring to the University of Munich. After completing one semester at Munich, Lewin transferred again—this time to the University of Berlin, where he remained until he completed his Ph.D. He took courses in philosophy instead of medicine, and found himself particularly attracted to the philosophy of science. One of Lewin's teachers suggested that he might find psychology interesting, and it was this suggestion that led to Lewin's work in the Psychological Institute of the University of Berlin. When the time came for Lewin to choose a director for his dissertation, he requested Carl Stumpf (1848–1936), who was the director of the university's Psychological Laboratory. Stumpf was a pioneer of the experimental method in psychology, which brought him into conflict with the reigning school of psychology in Germany in the 1890s. In addition to Stumpf, the other professor who made a deep impression on Lewin was Ernst Cassirer (1874–1945), who taught courses in philosophy of science. Lewin always admired Cassirer for encouraging him to push beyond the boundaries that limited the study of psychology at that time.

While in graduate school, Lewin became involved with socialist groups that advocated a democratic government for Germany as well as legal and professional equality for women. He formed a group of nine or 10 students who organized evening classes for working-class men and women in subjects ranging from arithmetic and reading skills to history and geography. The informal "school" continued to enroll more and more students each year until the outbreak of World War I.

World War I and early career

Although Lewin was not eager to go to war, he volunteered to serve in the Kaiser's army after World War I broke out in 1914. He had already completed the requirements for his doctorate, but the degree itself was not conferred until 1916. Lewin served throughout most of the war, working his way up to the rank of lieutenant. He was wounded in 1917 and hospitalized, but his younger brother Fritz was killed in action. While Lewin was recovering, he published his first journal article, "Kriegslandschaft" or "War Landscape," which was a preview of several of the concepts he developed in his later work, such as "life space," "boundary," and "zone." That same year, he married Maria Landsberg, a close friend of his best friend's wife. Maria taught English and German in a high school for girls.

The years between 1917 and 1921 were full of turmoil for German academics. In 1918, the Kaiser abdicated and fled to the Netherlands as the German army was defeated in France. Part of the Kaiser's former palace was used to house the University of Berlin, and the Psychological Institute was given several rooms to use for lectures and research. In 1921 Lewin was appointed a Privatdozent or university lecturer, but this position did not carry a salary; Privatdozenten were paid directly by their students. Lewin was well liked by his students, however, as he was much less formal than most European academics and encouraged his students to develop their own ideas. It was during this period also that Lewin began to add mathematical formulae and blackboard diagrams to his lectures. He taught courses in philosophy as well as psychology, and after 1924 began to supervise doctoral candidates as well. At a time when women were still not fully accepted in European universities, Lewin had an unusually large number of female doctoral candidates, many of them from the Soviet Union.

PRINCIPAL PUBLICATIONS

• "Kriegslandschaft" [War Landscape]. Zeitschrift für angewandte Psychologie 12 (1917) 440–447.
• Der Begriff der Genese in Physik, Biologie und Entwicklungsgeschichte [The Concept of Origin in Physics, Biology, and the History of Evolution]. Berlin: Julius Springer Verlag, 1922.
• A Dynamic Theory of Personality: Selected Papers of Kurt Lewin, translated by Donald K. Adams and Karl E. Zener. New York: McGraw-Hill Book Company, 1935.
• Principles of Topological Psychology. New York: McGraw-Hill Book Company, 1936.
• Resolving Social Conflicts: Selected Papers on Group Dynamics, edited by Gertrud W. Lewin. New York: Harper and Row, Publishers, 1948.
• Field Theory in Social Science: Selected Theoretical Papers, edited by Dorwin Cartwright. New York: Harper and Brothers, 1951.

Lewin first came to the attention of British and American psychologists through J. F. Brown, an American who studied with him in Berlin. Brown published a paper on Lewin's methods in an English-language journal in 1929. Lewin had also been invited to give a lecture to the International Congress of Psychology, which met at Yale University in Connecticut in 1929. Lewin brought along a short film he had made of an 18-month-old child—his wife's niece—to illustrate some of his concepts. Even though he lectured in German, his ideas were so interesting that several American students came to Berlin in 1930 to work with him, and two of them translated several of his articles for republication in English. A collection of these translated articles was published in the United States in 1935 under the title A Dynamic Theory ofPersonality. By that time Lewin had left Germany permanently.

Move to the United States

Lewin's work at the Psychological Institute came to an end when Hitler's rise to power led to riots that temporarily closed the University of Berlin. Lewin had been invited to Stanford University in California in 1932 as a visiting professor. When Hitler became chancellor of Germany in January 1933, Lewin realized that he and his family were no longer safe in their homeland because they were Jews. He resigned his professorship at the University of Berlin and returned to the United States in August 1933, when he was offered a two-year position at Cornell's School of Home Economics. When the Cornell appointment ran out in 1935, Lewin accepted a position at the Child Welfare Research Station at the University of Iowa, where he remained until 1944. Although Lewin was still struggling with learning English, he was again popular with students, gathering an informal weekly lunchtime meeting that the students nicknamed "the Hot-Air Club." He had a lively sense of humor and enjoyed telling jokes; in addition he never rejected students or colleagues for disagreeing with him. One of Lewin's colleagues later recalled,

people could move out of Lewin's immediate circle even during his lifetime and still maintain ties with him and others in his circle.... I think Kurt was quite right in saying that he didn't want to develop a school of psychology; he was merely trying to develop a language for the representation of psychological phenomena.

While at Iowa, Lewin built a reputation as an outstanding experimental as well as theoretical psychologist. Some of the studies he undertook during this period are described under "Theories in action" below.

The fact that Lewin came to the United States from a very different academic as well as national culture gave him a fresh perspective on his new country. He was particularly interested in the question of different national characteristics. In 1936, he published an article still regarded as one of his finest—"Some Social Psychological Differences Between the United States and Germany," which appeared in the journal Character and Personality. Among other points, Lewin contrasted the degree of independence in American children and "the lack of servility of the young child toward adults or of the student toward his professor," with the behavior of their German counterparts. He also noted the relative openness of American adults compared to Germans. In view of Lewin's later work on social groups and group membership, it is interesting that he was determined to become an American—which for him meant much more than formal citizenship, though he was certainly delighted when he became a citizen in 1940. He set about improving his English as quickly as he could, even though he never completely lost his German accent. When he noticed that his children were confused by the difference between the German pronunciation of their last name ("Luh-veen," with the accent on the second syllable) and the way their American teachers pronounced it ("Loo-in," with the accent on the first), Lewin asked his colleagues to pronounce his name the American way. His biographer tells of an incident at the World's Fair in New York in 1939, when dinner hour approached, both men were getting hungry, and the restaurants on the fairgrounds were already full. "'Let's have a couple of hot dogs,' Lewin said. 'That's what we Americans eat on Sunday evenings in the summer!' Five minutes later that's what we were doing."

Lewin brought his long-standing concern with social issues to bear on solving industrial problems during the late 1930s. Many of his first experiments with action research began during this period. The problems that Lewin and his colleagues tackled ranged from helping inexperienced factory workers raise their production levels, to training foremen and supervisors in leadership skills. One of Lewin's associates at Iowa, a psychologist named Alex Bavelas, set up a series of small-group studies at a factory in Virginia that ran from 1940 to 1947. These studies are described in more detail below. The experience that Lewin and his group had in teaching leadership skills was eventually put to use in later sensitivity training programs.

Wartime work

After the United States entered World War II in December 1941, psychologists as well as scholars in other fields were sought out by government officials to help solve problems related to the war effort, and to come up with better methods of measuring and analyzing results. Psychologists in particular were consulted about such questions as maintaining morale on the home front, improving leadership training in the military, and solving human relations issues in offices and factories in order to boost production. The Office of Naval Research (ONR) contacted Lewin and his group at Iowa to review research proposals and provide feedback on general ONR policy. In addition, Lewin advised the Office of Strategic Services (OSS) on psychological warfare. As of the 1980s, some of his contributions in this area were still considered classified information.

Lewin's wartime work involved frequent trips to Washington, which caused some tension with his colleagues in Iowa. In addition to disagreeing with his theories, some other faculty members resented his frequent absences from the campus, his smaller teaching load, and his growing reputation outside the academic community. Lewin also had growing doubts as to whether Iowa was the right place for carrying out some experiments that he wanted to do in the field of group dynamics, a subject that had captured his attention early in the war. He was convinced that psychologists needed to do more than simply look for explanations of people's behavior. In an article published in 1945, Lewin stated, "We must be equally concerned with discovering how people can change their ways so that they learn to behave better." These discoveries, however, depended on experimentation.

As Lewin became more committed to action research, he began to think about setting up a research institute associated with a university that would not be controlled by the university. After a possible job offer from the New School for Social Research in New York fell through, Lewin approached several foundations for funding for his proposed institute. He also thought about possible locations for it—he wanted it to be related to a university in a large city with a variety of community, racial, religious, and industrial problems that could serve as a laboratory for action research. In 1944, Lewin finally received an invitation to set up his institute at the Massachusetts Institute of Technology. It was called the Research Center for Group Dynamics. At the same time that Lewin was beginning to staff the new Center, he launched another new project, the Commission on Community Interrelations (CCI) for the American Jewish Congress (AJC). The purpose of the CCI was to investigate the roots of prejudice against Jews. Lewin expected that the research undertaken by the CCI would benefit all minority groups in the United States, not only Jews; as he put it in a letter to a well-known rabbi, "The fight of the Jews is a part of the fight of all minorities for democratic equality of rights and opportunities."

Lewin hoped to get the new Research Center at MIT ready by the fall of 1945, since the war had ended in August with the surrender of Japan. He had been able to attract additional funding from the National Institute of Mental Health, the Air Force, and the Rockefeller Foundation, which allowed him to enlarge the teaching staff. The Center supported six major areas of research: group productivity, communication, social perception, intergroup relations, group membership and individual adjustment, and leadership training. Within less than a year, students from many other countries as well as the United States were enrolling in courses at the new Center.

In spite of Lewin's busy schedule at the Center, he continued his involvement with the CCI, which had broadened its scope to include interracial problems as well as religious prejudice. He was also consulted about a project begun by the Connecticut State Interracial Commission to train leaders who could help resolve racial and religious tensions. Lewin designed a two-week workshop in 1946 to train 41 community leaders for the Connecticut program. This workshop led within months to the establishment of the National Training Laboratories, or NTL, in Bethel, Maine, in the summer of 1947. The technique of leadership training that Lewin pioneered in 1946 is considered by some psychologists to be "the most significant social invention of [the twentieth] century."

The many projects that Lewin took on during and after the war strained his health and energy. His friends urged him to slow down, but he insisted on keeping up his busy schedule. On February 11, 1947, Lewin went home for dinner and told his wife he felt ill. She called the family physician, who diagnosed a mild heart attack. Before the doctor could get Lewin to the hospital, however, he suffered a second attack and died. He was not yet 57 years old.

Marriages and family

Lewin's 1917 marriage to Maria Landsberg ended in divorce in 1927. The couple had had two children—a daughter, Agnes, born in 1919; and a son, Fritz, born in 1922. The marriage was strained by Lewin's work habits—he had an irregular work schedule in addition to being frequently away from home—and by Fritz's childhood illness. Fritz had been slow in learning to walk, and the family physician discovered at that time that he had been born with both hips dislocated. Two major operations were required, one on each hip joint, with a long recovery period in between. In addition, Agnes began to develop emotional problems related to the family's focus on her brother's health. Although both parents were devoted to the children, they could not agree on the best way to deal with these issues. Lewin moved out of the home, but continued to visit his children and former wife until they moved to Palestine when Hitler came to power.

In 1929 Lewin married Gertrud Weiss, whom he and Maria had known since 1921. They had two children—Miriam, born in 1931; and Daniel, born in 1933. Miriam became a clinical psychologist in her own right; among other publications, she wrote a handbook for student researchers in psychology as well as a historical account of psychologists' views of gender roles.

One of the tragedies of Lewin's last years was his inability to rescue his mother, who had remained in Berlin after Lewin left Germany. After Hitler invaded Poland in September 1939, Lewin tried to bring his mother to the United States, but was unable to obtain a visa for her. Recha Lewin was sent to a concentration camp somewhere in Poland in 1943, where she died in 1944. Several of Lewin's friends believed that his personal sorrows contributed to his untimely death. He turned his private pain, however, into compassion for other victims of prejudice and discrimination, and he never lost his faith in a better future for all people.

THEORIES

Field theory and the structure of human personality

Main points Lewin's theories in general are difficult for new psychology students for several reasons. One is that he coined a number of new terms and expressions, such as "life space" and "foreign hull." In addition to new terms, Lewin also used such familiar words as "locomotion," "fact," "event," and "tension" in unfamiliar ways. Lewin also borrowed mathematical and scientific terms, including "vector," "force," and "valence." As a result, Lewin's articles are not easy reading.

Lewin is well known in the history of psychology for his field theory. Field theory is a term that was originally developed by physicists in the 1870s to account for what happens when a number of different forces interact. The physicists began to refer to these collections of forces as energy fields. Lewin came to regard the human mind as a complex energy field containing tension systems in various states of equilibrium, or balance. He then defined human behavior as a change in the state of this energy field. Lewin begins with the life space, which includes all the possible facts that may influence a person's behavior at a given point in time. "Real-world" facts are important only to the extent that they are psychologically important to the individual. Lewin summarized his concept of behavior as a function of the life space in a mathematical formula: B = f (LS). He also represented the life space by a drawing known as a Jordan curve, which is an irregular closed curved line resembling an egg or ellipse. The curve itself is the boundary that separates the person from the parts of the real world that are not psychologically significant to him or her. Inside the Jordan curve is a smaller circle containing a P, which represents the person. The circle is inside the ellipse but does not touch it. The area outside the circle but inside the ellipse is called the psychological environment. The total area inside the Jordan curve, including the circle, is called the life space. The area outside the ellipse is called the foreign hull. Lewin invented the term "topological psychology" to describe these geometrical drawings, topology being the branch of geometry that deals with the properties of geometric figures that do not change when the figure is bent or stretched.

Lewin's diagram of the life space includes several subdivisions. The circle representing the person can be subdivided into two concentric circles. The inner circle represents what Lewin called the inner-personal region, and the outer ring is the perceptual-motor region. Similarly, the psychological environment surrounding the circle can be divided into regions, which represent possible intellectual, physical, or social activities. Lewin refers to the principal facts in the person's inner-personal region as needs, and the corresponding facts in the psychological environment as goals. Needs control the person's behavior and are satisfied when the person achieves his or her goals. Goals are related to needs by either a positive or negative attraction, which Lewin called a valence. To give an example of what Lewin meant by a valence, a warm sweater would have a positive valence for someone sitting motionless outside on a cold day, while the same sweater would have a negative valence for someone playing a fast game of tennis on an outdoor court in mid-July.

According to Lewin, people tend to move psychologically toward entities in their life space that have a strong positive valence, and away from those with a negative valence. He called these movements locomotions. Lewin did not use the word "locomotion" to refer primarily to a physical movement through space, but a movement through the psychological environment within a person's life space. Thus there are many different types of locomotions: a person might move toward an answer in solving a crossword puzzle, or move away from depressing thoughts by calling a friend, or move toward higher social status by joining a prestigious club. All of these psychological movements are locomotions as Lewin used the word. A locomotion in the life space might entail physical movement in the outside world—as when a hungry person decides to leave their house and go to a nearby restaurant—but the locomotion itself is the person's psychological movement toward food. Behavior to Lewin is always goal-directed, and therefore always involves locomotion toward or away from goals within the life space.

Locomotions through the life space, however, may be prevented by barriers. To Lewin, a barrier is anything that the person perceives as a block or resistance to locomotion toward a goal. An example of a barrier would be a person's fear of another family member's reaction to their choice of a movie for a family outing. Another type of barrier would be the obstacle posed to medical school admission by failing a college course in chemistry.

Explanation Lewin's basic approach to questions of personality was derived from Gestalt psychology, which will be described more fully in a later section. The central point of Gestalt psychology for present purposes is that human perception is shaped by the total context of individual objects; that is, people perceive relationships among the various objects that they are looking at rather than the characteristics of each item by itself. Another way of putting the matter is that people do not perceive separate objects directly but rather impose an organizational pattern on them in their mind. Commonplace examples include the fact that people often "see" some kind of shape or pattern in cloud formations, or the way in which astronomers group individual stars into constellations. In contrast to behaviorist psychologists, who began with collecting masses of data and analyzing them from the bottom up, so to speak, Lewin and other Gestaltists began with the overall pattern or shape of a field, and then proceeded to study its smaller components. Lewin's field theory thus takes in everything in a person's life that is psychologically important to him or her, and organizes all the elements in that life—goals, needs, behavior, tensions, forces, etc.—into a single system of description and explanation. In addition, field theory holds that all the elements in the life space are interdependent and influence one another.

In addition to the influence of Gestalt psychology on Lewin's field theory, it is also important to understand that Lewin saw his drawings of egg-shaped curves and enclosed circles as more than just blackboard illustrations for teaching purposes; to him they were maps of reality itself. As Lewin's biographer expressed it, "The Jordan curve . . . is a conceptual representation of reality which can serve as a map to guide the psychologist." Other psychologists, however, disagreed with Lewin's own estimation of his topological psychology; their criticisms are discussed more fully below.

Examples An example of Lewin's use of language as well as his way of diagramming his ideas is found in a 1946 article entitled "Behavior and Development as a Function of the Total Situation." Lewin's diagram represents a state of indecision, in this case a child who must choose between two goals, each with a positive valence. Perhaps the child has to choose between playing with friends and going to a movie with the rest of the family. Lewin maintains that "the person being in the process of making a decision usually alternates between seeing himself in a future situation corresponding to the one and the other possibility." Two Jordan curves are used to diagram these hypothetical futures, with the decision identifying the overlapping region.

Tension systems and the dynamics of human personality

Main points Lewin's field theory utilizes the concept of tension systems in order to explain human personality in action. In essence, a tension system is an energy system created by a need and released when the person achieves the goal related to that need. Lewin does not use the word "tension" in the sense of an undesirable stress or emotional strain; rather, he regarded tension as a desirable condition of readiness for action toward attaining a goal. He saw tension as increased by any barrier between the need and the goal. In addition to barriers, Lewin also related tensions to forces. Lewin distinguished three types of forces: driving forces, which arise from needs and cause locomotion toward a goal; restraining forces, which are associated with barriers; and induced forces, which are related to the wishes of other people in the person's life space. Lewin regarded forces as having both direction and strength, and represented them in his drawings as vectors (arrows), with the direction of the vector representing the direction of the force, and its length representing its intensity or strength. An inner-personal conflict results when the driving forces that affect a person come from different directions and are about equal in strength. The conflict may concern one negative and one positive goal, or two equally negative or equally positive goals.

Lewin maintained that tension tends to equalize itself by spreading from one region throughout a person's psychic system; he called the means of this equalization a process. Processes include such activities as thinking, remembering, perceiving, performing an action, and many others. Several different tension systems and processes may coexist simultaneously within a person and remain for various lengths of time. A simple example of what Lewin meant by process and the equalization of tension systems is a person who notices an itchy area between the shoulder blades at the same time that he is trying to balance his checkbook. The person may decide to interrupt his calculations in order to satisfy the need to scratch his upper back. After the tension in that part of his psychic system subsides, the person returns to his checkbook in order to fulfill his need to complete the interrupted task.

Lewin was not completely satisfied with the word "need" to explain increases in psychological tension. He used the word as a rough equivalent for "motive," "wish," or "urge." In Lewin's usage, a need is not limited to such physical conditions as hunger or thirst—it could include intentions (to finish a project), purposes (to get on the football team), or desires (to go for a walk outside on a nice day). Lewin never tried to reduce all human needs to one basic need as some psychologists did, although he did distinguish between needs derived from such bodily conditions as hunger, thirst, or feeling cold, and what he called quasi-needs, which include purposes and intentions. Lewin thought that quasi-needs are by far the more common type in everyday life.

Explanation Lewin developed his concept of tension systems in part because he disagreed with the associationist explanation of human behavior. Associationist psychologists explained behavior as the end result of simple ideas derived from sense experience that became associated in the mind through repetition and conditioning. An associationist psychologist would regard doing any purposeful action as setting up a tendency to repeat the action. Lewin observed that there are many purposeful actions that people do not ordinarily repeat once they have achieved their goal. For example, a person who goes into the kitchen to pour themselves a cup of coffee does not automatically brew themselves another cup the next time they walk into the kitchen. On Lewin's account of the matter, the tension created by the person's desire for a cup of coffee is released by the act of going into the kitchen and filling their cup, which is why returning to the kitchen a few moments later to feed the cat or wash the dishes does not lead to making or pouring another cup of coffee. The psychic energy related to the first need has been released, and the other tension system(s) are now in the forefront of the person's attention.

Another important feature of Lewin's concept of tension systems is his emphasis on the here-and-now. He parted company with Freudian psychoanalysis in looking for long-term historical explanations of human behavior. Lewin argued instead for what he called the principle of contemporaneity in a person's life space, meaning that only present facts can influence present behavior. The facts of a person's infancy or childhood cannot affect adult behavior unless they have remained alive in some sense as the person matured. In one of his early articles entitled "On the Structure of the Mind," Lewin drew on his own experience as the basis for the principle of contemporaneity:

Twenty-five years ago I awoke, happy that I did not have to go to school that day, I flew a kite . . . ate a great deal of dessert, and played in the garden . . . each single everyday experience of the past may somehow influence the present psychic life . . . but ... the influence is extremely small, approximately zero. ... Behavior would not be changed or would change imperceptibly if a great many of our experiences did not occur or occurred in other ways.

Lewin thought that Freud and his followers failed to distinguish between historical and systematic problems in psychology, "more or less consciously preferr[ing] richness of content to logical strictness of theory.... In other words, psychoanalysis is a body of ideas, rather than a system of theories and concepts."

Examples Lewin's theory of tension systems received its first experimental proof in a casual afterhours setting. During his years in Berlin, he would often go with his students to a nearby café, where they would sit for hours discussing their work over coffee and slices of cake. The waiters did not keep written notes of the customers' orders, but could easily give a correct account to each member of a group when the bills were called for, even though the group might have been in the café for two or three hours. Lewin began to think that the waiters' memories were kept sharp by a tension system building up that was not released until a group of customers called for their bills. The next time that the group visited the café, Lewin waited for about half an hour after his students had paid their bills, and asked the waiter to rewrite the group's check. The man was annoyed by Lewin's request and said "I don't know any longer what you people ordered. You paid your bill." This informal proof of Lewin's theory led to his student Bluma Zeigarnik's famous experiment and the naming of the so-called "Zeigarnik effect," namely, that people are better at remembering uncompleted than completed tasks.

Bluma Zeigarnik's discussion of task interruption and recall is now considered a classic. Her dissertation was published in 1927 in the Psychologische Zeitung (Journal of Psychology), which was sponsored by the University of Berlin. Lewin summarized her experiments in an article that appeared in English translation in 1935. Zeigarnik conducted a series of experiments between 1924 and 1926 involving 164 subjects, adults as well as children. She gave the subjects about 20 simple tasks, such as making a list of cities, answering riddles, counting backwards, stringing beads, and doing other paper-and-pencil exercises. In the first experiment, the subjects were allowed to complete half of their tasks, while the other half were interrupted before they had finished. After some time had elapsed, Zeigarnik asked her subjects to remember as many of the tasks as they could. She found that they remembered uncompleted tasks better than completed tasks by a ratio of 1.9 to 1. She also found that her subjects were more than three times more likely to list one of their unfinished tasks first than one that they had been allowed to finish without interruption.

Zeigarnik then decided to test the possibility that her subjects' memory was related to the surprise of being interrupted rather than the state of their tension systems. She ran a second experiment in which she interrupted her subjects in one-third of their assigned tasks, allowed them to finish another third without interruption, and interrupted them during the final third but then allowed them to complete the unfinished tasks. Zeigarnik's results showed that the memory of the subjects in the second and third groups was almost identical, which indicated that it was not the interruption by itself but leaving the task unfinished that was the critical factor. Zeigarnik had successfully demonstrated that memory is related to unreleased tension systems.

Action research

Main points Lewin's interest in what he termed action research, or applied social psychology, began during his last years at Iowa. His role as a consultant in several factories with production problems also stimulated his work in this area. Action research as he defined it begins with an identifiable social problem—for example, racial prejudice in a specific neighborhood or small town. Lewin outlined the basic steps or phases in action research in his 1946 article "Action Research and Minority Problems." The first stage is defining the problem and "examin[ing] the idea carefully in the light of the means available." The second step involves fact-finding and forming an overall plan for reaching the goal, along with a first step toward the goal. Lewin notes that "Usually this planning has also somewhat modified the original idea." The second phase consists of "executing the first step of the overall plan," followed by a second round of "reconnaissance or fact-finding."

Lewin stated that the second phase of fact-finding served four important purposes:

• Evaluating the success of the first step, "whether what has been achieved is above or below expectation."
• Giving the planners a chance to learn and gather new insights.
• Helping to plan the next step.
• Providing a basis for changing the overall plan.

The third phase of action research consists of another cycle of planning, acting, and fact-finding. These steps are repeated as often as necessary until the goal has been reached. Lewin summarized the process: "Rational social management, therefore, proceeds in a spiral of steps each of which is composed of a circle of planning, action, and fact-finding about the result of the action."

Explanation Lewin's concept of action research has two important features. The first is that Lewin thought of action research as a group activity rather than an individual undertaking, which is reflected in some of its other names: participatory research, collaborative inquiry, and contextual research. This emphasis on group involvement in action research is in part a reflection of Lewin's own personality. He enjoyed the companionship of others and preferred to work with them rather than being a "lone ranger" type of researcher. His friends described him as a cheerful, even playful person; as a man who delighted in telling jokes or inviting people to his home for dinner on short notice. On the last night of Lewin's life, he told a colleague named Ronald Lippitt that a person's competence should not be defined in terms of "going it alone." Lippitt recalled Lewin as saying:

The American ideal of the 'self-made man' . . . was as tragic a picture as the initiative-destroying dependence on a benevolent despot. We all need continuous help from each other. This type of interdependence is the greatest challenge to the maturity of individual and group functioning.

In addition to the factor of Lewin's own personality, he emphasized teamwork in action research because his own interests had shifted in the late 1930s from the psychology of individuals to that of groups. After the early 1940s, Lewin published very little new work on personality theory; he was now interested in constructing a general theory of group processes—how groups set standards, select leaders, reach decisions, and similar issues.

The second feature is the relationship of action research to Lewin's strong commitment to egalitarianism and democracy. "Learning by doing" was one of philosopher and educator John Dewey's foremost principles of educational method, and Lewin incorporated Dewey's perspective into his own work. As will be evident in one of the case studies under "Theories in action," Lewin's involvement in studies of race relations and religious prejudice sparked a number of action research projects.

Examples An early example of Lewin's action research took place in the 1940s, when he served on a wartime committee that investigated American tastes and habits in food consumption. While the government's chief concern was to maintain the health of the civilian population during a period of food rationing, rising expenses, and necessary shifts in the kinds of foods available to the public, Lewin recognized that eating habits are only one specific part of a much larger question—namely, how are social changes brought about within groups and by groups? Lewin set up a series of experiments to test the ways in which different families in the Midwest and New England differed in the foods they chose, and which members of the family had the greatest influence on these decisions. One experiment concerned persuading housewives to purchase so-called variety meats (the internal organs, feet, and tails of butchered animals) instead of the more expensive rationed cuts of meat. Lewin discovered during this experiment that the wives determined food choices rather than their husbands, even though the women had said at the beginning of the study that their husbands made the decisions. Lewin concluded that the most effective way to promote greater use of variety meats on the home front was to convince the wives rather than the husbands that people could enjoy eating these less expensive meats.

One of Lewin's first community-related action research projects took place at the request of the CCI in 1946. It concerned an incident of religious prejudice in Coney Island, New York, in which a gang of four Italian Roman-Catholic boys had created a noisy disturbance during Yom Kippur services at a nearby synagogue. At the time of this incident, Lewin had only two assistants on his staff, but he quickly recruited a task force of psychologists that included Protestants and African Americans as well as Roman Catholics and Jews. All the members of the task force had been trained in human relations. The group's first action step was to stop a lawsuit against the four boys, who were then placed under the supervision of their parish priest and a group of Catholic Big Brothers. Lewin's group then made a survey of community attitudes, interviewing as many local people as they could. The researchers found that the boys were not angry at Jews in particular but felt angry and frustrated about life in general. The neighborhood as a whole felt that better housing, transportation, and recreational facilities would help ease tensions among the different racial and religious groups. The task force's findings were reported to the Mayor of New York, who earmarked some funds for the needed improvements. One member of the CCI staff was assigned to work closely with the four boys. A year later, CCI was able to report to the mayor that the gang members had virtually stopped their street fights and bullying of other people. The final measure of the project's success was that the gang members did not return to their former behavior even after CCI's consultancy ended.

Groups and change processes

Main points Lewin was interested in group processes for both theoretical and practical reasons. On the theoretical level, he thought that a solid body of knowledge, once collected, would allow him to form a general theory that would fit any group—marriages, nuclear and extended families, workplace groups, religious congregations, and community organizations. He understood group behavior as a function of both individual members and social contexts. From a historical perspective, Lewin was in the right place at the right time, as specialists in such fields as industrial management, group psychotherapy, and education were convinced by the mid-1940s that they needed to do more studies of group functioning. Lewin's first use of the term "group dynamics" appeared in a 1939 article called "Experiments in Social Space," in which he said that the purpose of his experiments was "to give insight into the underlying group dynamics."

Two key concepts regarding group process emerged from Lewin's field theory, namely interdependence of fate and task interdependence. As was mentioned in the preceding section, Lewin regarded interdependence in general as an essential feature of individual as well as group maturity. Interdependence of fate was a concept that Lewin used to explain the existence of groups that come into being "when people in [the group] realize that their fate depends on the fate of the group as a whole." Writing in 1946, Lewin described the Jews as an instance of this type of interdependence.

It is not similarity or dissimilarity of individuals that constitutes a group, but interdependence of fate.... It is easy enough to see that the common fate of all Jews makes them a group in reality.... A person who has learned to see how much his own fate depends upon the fate of his entire group will be ready and even eager to take over a fair share of responsibility for its welfare.

Other examples of interdependence of fate would include groups of people engaged in dangerous activities, such as the members of mountain climbing expeditions or space shuttle crews.

Lewin recognized, however, that interdependence of fate by itself does not form strong bonds among the members of most groups. He regarded task interdependence as a stronger "glue" in keeping the members of a group together. Using the concept of tension systems from his field theory, Lewin argued that the tension within group members created by desires for a common goal resulted in interdependence in order to achieve the goal. He was not convinced by the psychoanalytical explanation of group activity as the result of aggressive drives in some individuals belonging to the group. Rather, Lewin concluded that groups provide a setting for their individual members' sense of identity and social reality. "The group a person is a part of, and the culture in which he lives, determine to a very high degree his behavior and character . . . [as well as] his personal style of living and the direction and productivity of his planning." In a later article, Lewin said, "What exists as 'reality' for the individual is, to a high degree, determined by what is socially accepted as reality.... 'Reality,' therefore, is not an absolute. It differs with the group to which the individual belongs."

Lewin's theoretical understanding of group dynamics had practical applications in terms of social change. As World War II drew to a close, psychologists as well as researchers in other fields were concerned about rebuilding the social as well as the economic structures of the defeated Axis powers. Lewin's understanding of group dynamics was directly relevant to such issues as reintroducing democratic values in Germany and Japan, and doing it in such a way that these nations would not return to dictatorial political systems. Lewin believed that the democratic government of the United States depended on a certain "social atmosphere" more than pure reason or logic, and that this social atmosphere had to be protected and maintained by each successive generation.

The social climate in which a child lives is for the child as important as the air it breathes. . . . It seems to be 'natural' for people living in a thoroughly democratic tradition like that of the United States to believe that what is scientifically reasonable should finally become accepted everywhere. However, history shows . . . that the belief in reason as a social value is by no means universal, but is itself a result of a definite social atmosphere.

Lewin's research in group dynamics led him to conclude that social change must be brought about in and by groups rather than forced on people as individuals. One of his most famous psychological experiments involved two groups of schoolchildren who were asked to complete a task (making masks for a school play); one group in a democratic atmosphere and the other group directed by an autocratic adult. The results of the experiment convinced Lewin that democracy not only requires voluntary participation in groups, but is best learned through such participation. In "Cultural Reconstruction," an article that Lewin published in 1943, he observed:

It is a fallacy to assume that people, if left alone, follow a democratic pattern in their group life.... In democracy, as in any culture, the individual acquires the cultural pattern by some type of "learning." Normally, such learning occurs by way of growing up in that culture.

Attempting to answer the question of reconstructing German culture after the war, Lewin proposed to focus on the country's teenagers, with that age group's typical enthusiasm and interest in group activities.

The adolescent is at that age level which determines what the cultural pattern will be in the immediately following generation . . . transforming this very age level—which is full of enthusiasm and, in many respects, accustomed to cooperation—into cooperative groups for productive reconstruction in a radical democratic spirit might be one of the few chances for bringing about a change for democracy which promises permanency.

Explanation One factor that helps to explain Lewin's conviction that groups are more significant than individuals in bringing about and maintaining social change is that he saw groups as the molds of individual character. In an important essay on "Conduct, Knowledge, and Acceptance of New Values" (1945), Lewin maintained that the processes by which an individual learns bad or deviant behavior are the same as those that shape normal behavior. "What counts is the effect upon the individual of the circumstances of his life, the influence of the group in which he has grown up."

Given this position, Lewin argued that reeducation in any society is essentially a process of cultural change. He saw this change as having three major aspects or levels:

• Changing people's cognitive structure.
• Changing their values. This transformation usually requires dealing with prejudices and stereotypes.
• Changing people's outward behavior. Lewin recognized that change on this level requires a change in a person's feelings about members of other groups as well as changes in their thinking.

Lewin observed, however, that "acceptance of the new set of values and beliefs cannot usually be brought about item by item." To bring about this threefold change, the leaders of a society must establish what Lewin called an "in-group," which he defined as "a group in which the members feel belongingness." Lewin then postulated that

the individual accepts the new system of values and beliefs by accepting belongingness to a group.... The chances for [successful] reeducation seem to be increased whenever a strong we-feeling is created. . . . It is basic for reeducation that this linkage between acceptance of new facts or values and acceptance of certain of certain groups or roles is very intimate and that the second frequently is a prerequisite for the first.

Examples Lewin's work with organizational change and the first experimental T-groups is a good example of his lasting influence on later psychologists as well as his work with group dynamics. He is often referred to as the "grandfather" of organizational change for the studies he conducted in the early 1940s, and for his insistence that any theory of change had to take into account not only the organization, but also the individuals in the organization and its surrounding environment. Lewin argued that none of these factors can be understood in isolation from the others. One of his most frequently quoted remarks has to do with changing organizations: "If you want truly to understand something, try to change it." Lewin outlined his basic model of the steps involved in organizational change in "Frontiers in Group Dynamics," a paper published in 1947. He drew on field theory to explain his three steps, which he called "unfreezing," "moving the group to a new level," and "refreezing," or making the changes permanent. Unfreezing refers to changing the force field within the organization. Lewin had pointed out that stability in any group is the result of a balance between driving forces (for change) and restraining forces (against change), all of which can be represented by diagrams and mathematical symbols. Trying to change an organization by adding more driving forces usually results in a counterforce that maintains the status quo. Lewin had the insight that it is generally easier to unfreeze an organization's internal balance by removing restraining forces than by adding driving forces.

Lewin's three-step model of organizational change—particularly the notion of unfreezing—became an important part of the training groups, or T groups, that grew out of his experimental work with the Connecticut State Interracial Commission in the summer of 1946. As was mentioned earlier, Lewin and three of his associates at MIT had been asked to conduct a two-week workshop for 41 community leaders in dealing with racial prejudice; including learning skills in dealing with people and more reliable ways to change social attitudes. The workshop was held on the campus of a teachers' college in New Britain, Connecticut. Some of the participants lived nearby and went home in the evenings, while others remained on the campus. Since the trainers held nightly sessions in which they discussed their observations of the trainees, the trainees who were staying at the college asked if they could attend these meetings. Most staff members were reluctant to allow the trainees to join the meetings, but Lewin saw no reason why they should not hear the observers discuss their behavior. The observers' feedback—a term that Lewin had borrowed from electrical engineering—was eye-opening to the trainees. The second development during the evening came when one of the female trainees disputed a staff member's observations about her behavior. Her disagreement led to a four-way conversation that involved the trainer, another observer, the trainee, and Lewin himself. The new data that emerged from this conversation as well as the open discussion of different opinions changed the format of the evening meetings. After that night the evening meetings became the most significant learning sessions of the workshop.

Although Lewin died before the first National Training Laboratory in Group Development was held in the summer of 1947, his theories formed the basis of the NTL's work, particularly its so-called laboratory method. The laboratory method was intended to provide "basic skills training," conducted in small discussion groups (usually 10 participants) with an observer who reported his observations to the group members from time to time. The skills had to do with becoming an effective "change agent." By 1949 the name of the basic skills training groups had been shortened to "T groups," which became the model for the encounter groups of the 1960s, sensitivity training groups in the 1970s, and team-building groups in the 1990s. In the process, however, Lewin's original vision of the laboratory as a setting for basic research in social dynamics was gradually deemphasized, and replaced with a focus on individual and personal growth. In the process, NTL also acquired a business rather than a research mindset, to the point where it has itself become a large business as of the early 2000s.

Lewin's influence was clearly evident, however, in what are still considered the four basic elements of T-group training:

• Unfreezing. Unfreezing refers to disconfirming or challenging a person's belief system in order to motivate them to change. T-group trainers try to create settings in which people's present values and beliefs are challenged.
• Feedback. As Lewin used the term, feedback refers to adjusting a process in light of accurate information about its results or effects. Feedback in T groups has been found to be most effective when it is based on here-and-now events and observations, and when the person receiving the feedback can check with other group members to test its accuracy.
• Participant observation. T-group participants are expected to participate in group sessions on an emotional as well as intellectual level. The trainers and observers in Lewin's original 1946 workshop modeled this combination of emotional involvement and analytic detachment.
• Teaching aids. Lewin's diagrams and mathematical models were eventually replaced by handouts and video clips, but the basic principle of reinforcing learning in T groups by visual means is derived from Lewin.

HISTORICAL CONTEXT

Gestalt psychology

The most important intellectual influence on Kurt Lewin was Gestalt psychology, a German school of thought that developed in the late nineteenth century in opposition to associationist and behaviorist views. Psychologists in both these groups broke down psychological events into separate parts and then proceeded to analyze the parts without reference to the whole. The Gestaltists insisted that psychological events had to be interpreted as integral wholes. The German philosopher Immanuel Kant (1724–1804) is regarded as a forerunner of Gestalt psychology. Kant argued in his Critique of Pure Reason (1781) that human perception by its nature organizes data received from the body's sense organs into unities or wholes that the person can understand. Although Max Wertheimer (1880–1943) is usually regarded as the founder of Gestalt psychology, the term "Gestalt" was first used by the philosopher Christian von Ehrenfels (1859–1932) in a paper on "form qualities" (Gestalt Qualitaten in German) in music.

The German word Gestalt does not have an exact English equivalent; it has been variously translated as "form," "shape," or "figure." German also has a verb form, gestalten, which can mean "to take shape" or "to assume a form." Wertheimer first began to use the term Gestalt when he heard von Ehrenfels' lecture about music. He observed that such terms as "major" or "minor" are characteristics of full chords or musical phrases rather than isolated notes. Later, in studying the phenomenon of apparent motion (in which two alternately flashing lights are perceived as one light moving back and forth), Wertheimer maintained that the apparent movement of the lights cannot be reduced to simpler physical stimuli. He defined what came to be called the Gestalt law of minimum principle—people do not perceive what actually exists in the external world as much as they tend to organize their sensory experiences in the simplest possible way. Wertheimer also formulated several laws of organization to explain how people organize sense experiences into simple and coherent wholes.

The five most important Gestalt laws are:

• Proximity. People perceive items that are close together in space as a group of items.
• Similarity. People perceive items that look alike as a group.
• Good form. What this law means is that human perceptions tend to become as clear and as fully developed as possible. For example, people will generally see a triangle with a small piece missing from one side as a complete triangle.
• Closure. People usually make their sensory experiences as complete as possible. This law is reflected in Lewin's theory of tension systems and the resolution of tensions.
• Figure and ground. This law refers to people's tendency to organize visual perceptions by distinguishing between a focus of attention (figure) and a background.

Anti-Semitism

Lewin's life was affected by anti-Semitism on the professional as well as the personal level. The close and affectionate bond that he had with his parents is reflected in the fact that they continued to support him financially as well as emotionally when he changed his course of study from medicine to philosophy of science and psychology. The reason that their approval was significant is that Lewin was risking his future employment by preparing for a university professorship. Although he would have had no difficulty in finding work as a country doctor, he faced the same strong discrimination against Jews in the German universities that Freud had confronted. Lewin's parents knew that his chances of obtaining a full professorship with a decent salary were very low; nevertheless they supported their son's decision.

After Lewin moved to the United States, he recognized that anti-Semitism existed in his new country, even though it was much less organized and murderous than the state-sanctioned anti-Semitism of Nazi Germany and Soviet Russia. Many American universities had admission quotas for Jewish students in the 1920s and 1930s, particularly at the graduate and professional school level. In addition, some of the most prestigious hotels in the United States openly identified themselves as "restricted," which meant that they did not accept Jewish guests. There is a striking scene in Gentleman's Agreement, a movie released in the year of Lewin's death, in which an undercover reporter pretending to be a Jew in order to do research on anti-Semitism finds that the exclusive resort where he has made a vacation reservation refuses to honor it.

Lewin understood that much of American anti-Semitism had to do with the aftermath of World War I and the Communist revolution in Russia. The Immigration Act of 1924, which sharply reduced the number of immigrants from Eastern Europe, shut the primary escape route for Jews from those countries trying to escape the anti-Semitic policies of Stalin and Hitler. In addition, the economic hardships resulting from the Great Depression of 1933 led many unemployed Americans to look for scapegoats for their anger. The Midwest, in which Lewin and his family had settled in 1935, was a relatively isolated part of the country with a small Jewish population, and many of Lewin's new neighbors did not question conspiracy theories regarding the role of "East Coast Jews" in controlling the United States' money supply. Lewin published several articles between 1935 and 1941 dealing with the effects of anti-Semitism on Jewish Americans, such as "Psycho-Sociological Problems of a Minority Group" (1935), "When Facing Danger" (1939), "Bringing Up the Jewish Child" (1940), and "Self-Hatred Among Jews" (1941).

The significance of Lewin's work in this area is threefold. First, the effects of cultural prejudice on individuals allowed him to explore both the connections and the differences between his social theories and Freudian psychoanalysis. Although Lewin disagreed with Freud's emphasis on childhood experiences and his neglect of social factors in emotional disorders, Lewin allowed that individual differences do influence a person's response to prejudice directed against him or her. In an article entitled "Personal Adjustment and Group Belongingness" (1941), Lewin observed, "It is clear that not all maladjustments of Jewish individuals stem from their being Jewish. Jewish maladjustment has the same source as that of non-Jews." Lewin went on to say, however, that "It would be difficult to find a maladjusted Jew for whom being Jewish has not influenced the type and degree of maladjustment." He attributed this effect to two factors, the first being the relative mildness of anti-Semitism in the United States. In Lewin's view, the relative openness of American society created a situation of "unclarity," in which a Jew could not be sure whether being rejected for a job or club membership resulted from personal failure or anti-Semitism. He or she therefore would not be able to decide whether to work on overcoming personal shortcomings or to work on changing the social environment. Lewin thought that the unclear situation would cause the person to become "disoriented." "In other words, this unclearness necessarily leads to a disorganized emotional behavior in the area of self-esteem which is so important for adjustment and personality development." Lewin concluded that emotional problems in individuals are often related to membership in a marginalized group, because the person must identify with the group to which they belong at the same time that he or she learns to judge that group by "the standards and values of the more privileged majority." "It is clear . . . that an individual cannot be well adjusted without being clearly adjusted to his own group, because the group is the ground on which the individual stands socially and without firm ground and clear orientation no one can act in an organized way."

The second significance is that Lewin's experience of anti-Semitism led him to extend his insights to the problems of other minority groups. As has already been mentioned, he regarded the struggle of Jewish citizens for equal rights as part of the struggle of all disadvantaged minorities. Many of Lewin's action research projects were undertaken with the desire to understand the nature of prejudice in order to create ways to overcome it. One major limitation of Lewin's work, however, is that he did not distinguish between discrimination against groups that can be clearly identified by external bodily features (race, sex, age, physical deformity, etc.) and groups that are less easily identified on the grounds of visual appearance (homosexuals, Jews and other religious minorities, people with prison records, etc.) It was left to such later researchers as Erving Goffman to study the differences among various forms of prejudice.

The third significance of Lewin's response to anti-Semitism is that it provided a model for other social scientists seeking to bring their research to bear on real-life social problems. Chris Argyris, who was influenced by Lewin's example even though he was not one of his students, has said:

Lewin's work inspired me because it suggested a model that combined theory, empirical research, and relevance to reality.... Lewin had the skill to integrate scientific rigor with reality and for this reason became the first major model of social scientist-activist of the highest quality.

CRITICAL RESPONSE

Inadequate research

Lewin and his students were frequently criticized for publishing studies based on a relatively small number of subjects. Hoppe's study of aspiration, which is described below, used only 10 subjects, and the studies of leadership models and frustration in children, also described below, used only 20 and 30 subjects respectively. Lewin did not deny that studying a larger number of subjects would have improved the reliability of his findings, and added that "additional confirmation is always desirable." He also pointed out that his own results had always stood up well when his studies were replicated by other researchers. But he mentioned on another occasion, "I do not expect ever to live down the misunderstandings created by my attack on some ways in which statistics have been used in psychology."

Misuse of concepts from mathematics and physics

Lewin's colleagues blamed his use of topology to illustrate his theories for the fact that his work was underestimated during his lifetime. When he published Principles of Topological Psychology in 1936, the book received a number of harsh reviews. Some reviewers maintained that Lewin's diagrams were distractions that led readers away from his theories to his mathematical representations of them. He replied in an article on "Formalization and Progress in Psychology" (1940) that his main interest was not "formalization or mathematization." The value of these tools for psychology "exists only in so far as they serve as a means to fruitful progress in its subject matter, and they should be applied . . . only when and where they help and do not hinder progress."

A related criticism of Lewin's use of topology and mathematical formulae is that they do not add any new insights to the behavior they supposedly explain. In addition, they cannot be used to predict a person's behavior before it occurs; rather, Lewin's diagrams are after-the-fact representations of his data. Lewin admitted that this line of criticism had some validity:

It is true, however, that it is a clearer test of the adequacy of the theory if one can make predictions from it and prove these predictions experimentally. The reason for this difference seems to be that empirical data generally allow for quite a range of different interpretations and . . . therefore it is usually easy to invent a variety of theories covering them.

The diagram reproduced earlier as an example of Lewin's use of topology may also serve here to illustrate his critics' point. It is difficult to see what the mathematical formulae add to a verbal description of a situation of indecision. Moreover, the diagram has no predictive value. In order to indicate the child's decision, one of the two vectors would have to be measurably larger or longer than the other—which would imply that the outcome of the child's decision is already known to the psychologist drawing the diagram.

Inadequate attention to objective reality

Lewin's field theory was criticized from the early 1940s onward for its tendency to make the life space a closed psychological system without any clear

FURTHER ANALYSIS:

Group leadership models

Lewin's best-known series of experiments was conducted with Ronald Lippitt and Ralph White at the University of Iowa in the late 1930s. Known as the "Leadership and Group Life" study, it involved groups of children doing arts and crafts activities under different leadership styles. Lewin and his colleagues organized four groups of 10-year-old boys, with four adult leaders and a wide range of craft activities. All the boys in these studies were volunteers, and the groups were carefully matched for patterns of interpersonal relationships, intelligence, socioeconomic status, and a few other variables. The groups were led by an authoritarian leader, a democratic leader, or leader with laissez-faire style. Each group received a new leader every six weeks with a different leadership style. This second experiment lasted a total of five months.

The three leadership styles were described by Lewin and his colleagues as follows:

• Authoritarian: The leader determined all policy; dictated activity steps and techniques; dictated the work tasks and work companions of each member; remained aloof from group participation; was "friendly or impersonal rather than actively hostile."
• Democratic: The leader encouraged group discussions and decisions on all policies; suggested two or three alternative procedures for activities when asked for technical advice; allowed the group to decide on division of tasks and allowed members to choose their work partners; participated in group activities "without doing too much of the work."
• Laissez-faire: Leader allowed the group complete freedom, with no participation on his part. He supplied work materials but did not participate in work discussions or intervene in activities in any way.

The findings from both experiments were striking. Lewin summarized them in an article published in 1939:

• Autocratic groups. Boys in the autocratic groups tended to be either openly aggressive and rebellious or apathetic and submissive. Much of the aggression was directed at boys who became the group's scapegoats; none of it was directed at the autocratic leader. The submissive children, however, engaged in horseplay and wasting time when they were given a nonauthoritarian leader. The autocratic groups produced a larger quantity of masks than the democratic groups, but their masks were of lower quality.
• Democratic groups. These groups maintained high morale, with the boys behaving in a friendly manner toward the leader and one another. They were capable of working independently when the leader left the room. They produced fewer masks than the autocratic groups, but their work demonstrated more originality, and the masks were of higher quality. All but one of the 20 boys expressed a preference for the democratic groups at the end of the study; the one exception was the son of a military officer.
• Laissez-faire groups. These were the least productive groups, producing few masks, with those few of very low quality. These groups could not work by themselves when the leader was temporarily absent; they had a low level of group morale; the members could not cooperate among themselves; and they placed great demands on the leader. One striking finding was that some boys who had been in an authoritarian group became frightened and disturbed when they were given a laissez-faire leader.

Lewin was pleased with the outcome of the study in that it confirmed his convictions about the superiority of democratic systems of government. It also reinforced his belief that democracy must be reaffirmed anew in each generation, as he noticed that the change in the children's behavior from autocratic to democratic groups took longer than the reverse.

connection to the real world outside the person. Edward Tolman (1886–1959) argued that Lewin's field theory does not account for the ways in which the outside world produces changes in a person's life space or the ways in which the life space changes the outside world. Tolman himself attempted to add to Lewin's field theory by proposing three types of psychological variables: dependent variables (the behaviors or actions of a person), independent variables (the person's age, sex, genetic makeup, and present physical functioning; conditions of drive arousal; and stimuli from the external environment); and intervening variables, which connect the dependent and independent variables. In other words, the intervening variables explain how a stimulus from the external world and a person's emotional and physical condition interact to produce behavior.

Tolman proposed four sets of intervening variables:

• Traits. These include an individual's basic temperament and intellectual capacity, and are influenced by heredity.
• Needs.
• Belief-value matrix. This concept is considered Tolman's most important addition to Lewin's field theory. What Tolman means by this term is the individual's thought categories, cognitive skills, beliefs, and values. The belief-value matrix allows a person to make distinctions among various needs as they are experienced, to evaluate them according to their importance, and to scan or analyze the external environment in order to satisfy them. Tolman also thought that the belief-value matrix includes the values shared by the person's community, thus providing a link between the individual and his or her society.
• The behavior space, which depends on the first three intervening variables plus the stimulus from the outside environment.

A somewhat different version of Tolman's criticism of Lewin was made by Floyd Allport in 1955. Allport argued that Lewin's field theory confuses physical realities (the outside world) and psychological realities (the life space) because Lewin used his terms ambiguously. For example, Lewin often speaks of locomotions as mental movements, but he also refers to some locomotions as physical movements. With regard to barriers, Lewin sometimes describes them as internal constraints on a person's behavior—such as fear of other people's reactions to an intended behavior—but in other instances he is clearly thinking of physical obstacles as barriers. For example, in the published article on the experiment with frustration and regression in children described below, Lewin repeatedly refers to the screen or partition used to frustrate the children in the second phase of the experiment as a "barrier." The central point of Allport's critique is that Lewin's field theory tempts the psychologist to mix and confuse external physical factors and internal psychological factors within the same field. Allport maintained that the researcher must separate the two sets of factors conceptually in order to uncover the laws that govern their interactions.

Lewin's principle of contemporaneity

As has already been mentioned, Lewin defined his principle of contemporaneity in opposition to psychoanalytical explanations of a person's life history. As a result, some of his critics argued that he did not pay enough attention to the effects of the past on present behavior. Lewin replied that he did in fact include what he called the "psychological past" in the total field as part of the person's present "time perspective." He answered his critics in a 1943 article entitled "Defining the 'Field At a Given Time'."

The psychological field which exists at a given time contains also the views of that individual about his future and past. . . . His views about his own past and that of the rest of the physical and social world are often incorrect but nevertheless constitute, in his life space, the "reality-level" of the past.

The question remains, however, as to whether Lewin's notion of the psychological past is an adequate account of memory. Researchers who have studied such mental disorders as post-traumatic stress disorder and dissociative identity disorder (formerly known as multiple personality disorder) would argue that Lewin's theory does not allow for the effects of traumatic experiences on human personality. Since the early 1980s, neurologists studying the formation of memory traces in the human brain have discovered that traumatic memories are formed in a very different way from normal memories. The types of childhood memories that Lewin listed on occasion as examples of the unimportance of the past in a person's present life space are all pleasant or neutral memories.

Traumatic memories are different, and are related to changes in the structure and function of the brain itself. Under normal circumstances, memories are formed when a person's senses register sights, sounds, and other sensory information, and pass on these data to an almond-shaped structure in the temporal lobe of the brain called the amygdala (which takes its name from the Greek word for "almond"). The amygdala is the part of the brain that attaches an emotional meaning to the data provided by the senses. A nearby part of the brain called the hippocampus organizes the information relayed through the amygdala and combines it with previous information from similar events. For example, if a person is trying on several different types of perfumes at a cosmetics counter, the hippocampus will organize this memory according to previously established memory patterns of pleasant smells, perfumes, shopping trips, the specific department store, etc. Under normal circumstances, the hippocampus is able to form memories efficiently according to the emotional significance assigned to them by the amygdala.

In traumatic situations, however, this system breaks down; the hippocampus is overwhelmed, shuts down, and cannot process the upsetting memory or combine it in any useful way with other memories. The result is that traumatic memories are not stored as unified wholes, but as bits and pieces of bodily sensations and sensory images that are not related to other events in the person's life or even localized in time. These memory fragments may resurface whenever the amygdala is triggered by anything in the present that is vaguely related to the original trauma. Such symptoms of post-traumatic stress as flashbacks, in which the person feels as if he or she is reexperiencing the sights, sounds, smells, or sensations of the traumatic event, represent a chaotic invasion of the present by the past that does not fit Lewin's notion of the psychological past as relevant to the present life space.

Lewin's concept of democracy and action research

Although one of Lewin's most famous studies is said to have proven the superiority of democratic leadership to other leadership models, Lewin has also been criticized for not having developed his notion of this type of leadership beyond a rough sketch. Some of Lewin's colleagues noted that he combined an elitist view of leadership with an element of control. Although Lewin maintained that democracy cannot be forced on individuals, he recognized the existence of "a kind of paradox." Speaking (in 1943) of the need to reconstruct the culture of Germany after the war, Lewin said:

The democratic leader does not impose his goals on the group . . . the policy determination in democracy is done by the group as a whole. Still the democratic leader should "lead".... To instigate changes toward democracy a situation has to be created for a certain period where the leader is sufficiently in control to rule out influences he does not want and to manipulate the situation to a certain degree.

One of Lewin's associates at Iowa commented that Lewin's commitment to democracy reminded him of Freud's definition of reaction formation. "The autocratic way he insisted on democracy was a little spectacular. There was nothing to criticize—but one could not help noticing the fire and the emphasis." Ironically, Lewin was caricatured as often during his life as a "mere political propagandist" as he was criticized for an elitist view of leadership.

Some forms of action research that have evolved from Lewin's model since his death take issue with certain aspects of his approach. In general, action research fell out of favor with academic psychologists during the 1960s because it was linked to left-wing political activism. In the 1970s, however, action research was reintroduced into schools of education and organizational development as a way of improving classroom practice. As of the early 2000s, Lewin's original model of action research has produced at least three major variations: traditional action research, which is most closely identified with Lewin's work and generally takes a conservative approach toward organizational power structures; radical action research, which takes a Marxist view of society and works to overcome power imbalances within organizational structures; and educational action research, which follows Dewey's belief that educators should involve themselves in community problem-solving at the local level. University-based action researchers in this third group often work with teachers in nearby primary and secondary schools.

Traditional action research based on Lewin's examples is sometimes referred to as technical action research because it focuses on improving the efficiency or effectiveness of an organization. It is usually started by a person or group of people who are considered experts or authority figures because of their greater experience or training. Technical action research is essentially product-directed even though it involves all the members of a working group. It is concerned with gathering information that confirms or refines existing theories, and that can also be used to predict future outcomes.

Even within the field of technical action research, however, contemporary practitioners take issue with Lewin on two points: First, modern researchers regard group decision-making as an important matter of principle, not just as a technique. In other words, it is not only a means to bring about social change, but also inspires participants to commit themselves to action. Some psychologists think that Lewin's spiral model has misled others into thinking that using the spiral as a rigid template constitutes "doing action research." Second, Lewin's critics object to his notion that action research is a way of "leading" participants to a more democratic form of life. Instead of action research serving as a recipe for creating a democracy, they maintain that it should be seen as a way to carry out democratic principles in a research setting.

Organizational change

Lewin's unfreezing-change-refreezing model of organizational change has also been criticized in recent years. One reason is that Lewin's model assumes that a static condition, or being frozen, is the normal condition of organizations. Second, the model assumes that managers are able to control or direct the processes of change within the organization. The increased pace of change in the business world over the past few decades has called that notion into question. Such recent researchers as David Nadler and his associates have argued that change in the current organizational environment takes two forms, continuous and discontinuous. Continuous change can be understood in terms of Lewin's model. It is the type of change represented by quality improvement programs and characterized by planned changes in performance as well as products. Discontinuous change, on the other hand, is caused by such external forces as disruptions in global markets, new technology, and rising expectations on the part of customers. It cannot be controlled by managers and frequently produces a sense of day-to-day chaos and disorder within businesses. As a result, people at all levels of these organizations need to learn and take action at the same time, as the speed of discontinuous change does not allow for the staff training programs and other relatively slow responses built into Lewin's freezing-change-refreezing model.

THEORIES IN ACTION

Research

Lewin's theoretical work gained him early recognition in Germany as well as in the United States because it stimulated a remarkable number of experiments. As two American commentators on Lewin's studies have stated:

Few other theories of personality have been responsible for generating so much experimentation. Lewin himself, although he is known as a brilliant theoretician, was always a working scientist. He took the lead in formulating empirical tests of many of his basic hypotheses.... It is impossible to estimate the number of investigations that bear the imprint of Lewin's influence.... Whatever may be the fate of Lewin's theory in the years to come, the body of experimental work instigated by it constitutes an enduring contribution.

Lewin's early research into personality and motivation was revolutionary because these areas had been previously regarded as off-limits to psychologists; they were dealt with by the psychoanalysts, who in turn maintained that these issues could not be explored experimentally. Lewin and his graduate students at the University of Berlin showed instead that questions of personality and motivation could be studied in a laboratory. Second, Lewin thought that research in psychology should be guided by a systematic theory. This approach distinguished him from earlier psychologists, who had usually performed laboratory experiments unrelated to one another and then broke down the data they collected into smaller categories. Lewin was convinced that the older technique led to oversimplified concepts of human behavior that did not fit observable facts.

Lewin's belief that research should proceed within the framework of a theory did not mean, however, that he concocted theories out of thin air and then looked for facts to fit them. Tamara Dembo, one of his first graduate students at Berlin, explained Lewin's approach as follows:

He would say, "These are only the beginning concepts; we will have to find out more about them. We cannot do this [experiment] yet; this [other study] is possible to do," and so on . . . if you asked him, "How can one do this?" he would reply, "What's the problem? Let's first look at the problem and see whether any of this is possible." Those were the terms he thought in.

Another feature of Lewin's research that set him apart from his predecessors was the simplicity of the equipment he used for his experiments. Psychologists of the 1920s generally conducted their experiments with complicated machines and other expensive apparatus. Although Lewin enjoyed tinkering with and repairing laboratory equipment—he had a reputation at Berlin as one of the best repair technicians in the Psychological Institute—he used a minimum of equipment for his own work. The Berlin experiments that he conducted with his students were carried out with nothing more elaborate than pencils, papers, and simple games or tasks for the subjects to perform.

These experiments, which were conducted between 1926 and 1930 and published in the Psychologische Zeitung, have been described as "one of the most distinguished groups of empirical studies in the psychological literature." Lewin's analyses of the Berlin experiments were among the papers translated into English for publication in book form in 1935 as A Dynamic Theory of Personality. The students who carried out these studies for their doctoral dissertations included Bluma Zeigarnik, whose work on tension systems was described earlier, Tamara Dembo, Maria Ovsiankina, Vera Mahler, Sarah Sliosberg, Gita Birenbaum, Anitra Karsten, Sara Fajans, Sara Jucknat, Georg Schwarz, and Ferdinand Hoppe. It is noteworthy, given the prejudice against women in graduate education in both Europe and the United States in the late 1920s, that nine out of Lewin's first 11 students were women. The five major psychological categories that were investigated by Lewin and his students included recall of unfinished tasks; level of aspiration; substitution; satiation; and anger. These topics provided fertile ground for additional research after Lewin and several of his students emigrated to the United States.

Case studies

Level of aspiration One of the topics that was investigated by Lewin's graduate students at the University of Berlin was level of aspiration, which refers to a person's behavior in regard to setting goals and working toward them. Ferdinand Hoppe performed the first experiments in this area in 1930. He worked with only 10 subjects, maintaining that a deeper investigation of a small number of cases would be more fruitful than a wide-ranging statistical study. Hoppe set out to measure the effect of success or failure on the subjects' level of aspiration. He offered his subjects a number of tasks ranging from throwing darts at a target to problems in arithmetic; all the tasks were offered with achievement levels ranging from "easy" to "difficult." Once a subject had established a baseline level of performance, Hoppe would ask what score he was aiming for on the next test. This goal then became the subject's level of aspiration. If the subject failed to meet the higher goal, he frequently regarded his previous score as a failure, even though he had considered it a success on the initial test. In many cases, the subject would set a lower goal for the third attempt.

Hoppe found that his subjects' experiences of success or failure were not related to any specific level of accomplishment, but were linked instead to a goal that measured whether their performances could be considered positive achievements. Hoppe then discovered that the subjects' level of aspiration changed according to their level of performance; if they experienced success at a task, they raised their level of aspiration for the next attempt. When they failed, they generally lowered their aspiration level or stopped doing the task. Hoppe did not find any instances in which a subject lowered his level of aspiration after a success or raised it after a failure.

Hoppe's study was one of the most important of the Berlin experiments in that it led to immediate practical as well as theoretical results. More than any of the other studies from this period of Lewin's career, Hoppe's work stimulated a flood of additional studies in the area of goal setting, particularly with regard to its applications in education. Lewin himself observed that

The factors which determine the level of aspiration are of basic importance for learning. A child may permanently keep his level of aspiration too high or too low for his ability. Good students tend to keep their level of aspiration slightly above their past achievements, whereas poor students tend to show excessively high or excessively low levels.

Action research in an industrial setting In 1939, two years before the United States entered World War II, Lewin was asked to serve as a consultant to the Harwood Manufacturing Corporation, a new plant that had just opened in rural Virginia. The factory was having difficulty training 300 inexperienced apprentices who were eager to work but could not reach the output expected of apprentices doing similar work in plants in the industrialized Northeast. Lewin came to visit the plant that fall, beginning a relationship that lasted until his death in 1947. The Harwood managers were genuinely puzzled by their problems with the workers. On the one hand, the employees said that they liked their jobs, and they were paid much better than they had been as waitresses or domestic help; on the other, employee turnover was high. The supervisors had tried every method they knew to raise production, but nothing had worked.

Lewin began with a problem-solving session that drew on Hoppe's dissertation research on aspiration. Lewin deduced from his conversations with the workers that the production goals set by the company were so high in comparison with what the employees had been able to do so far that the goals had no reality for the workers; in other words, the difference was too great for them to try to meet the company's quotas. As a result, they did not feel any sense of failure in not meeting production goals. Lewin made three suggestions: first, the company should stop pressuring individual workers about quotas; second, the company should have the workers form small groups and then deal with the groups rather than with individual workers; third, the company should find a way to show the workers that the production quotas were realistic. The Harwood managers quickly put Lewin's proposals into action. To carry out Lewin's third suggestion, they brought in some experienced workers from a plant that was closing in a town about 40 miles from the Harwood factory. Within two weeks, the Harwood apprentices began to raise their output, as they saw that the experienced workers could easily reach the company's quota. They came to believe that they too could do what the experienced workers were doing.

Lewin made a number of visits to the Harwood factory, where he was well liked for his friendliness and sense of humor as well as his ideas. The workers enjoyed teasing Lewin about his initial problems understanding their heavy Southern drawl, and they were delighted when he began to use local slang expressions. In addition to visiting the plant himself, Lewin suggested that Harwood hire Alex Bavelas from the University of Iowa to conduct some experiments on human factors in a factory setting. Bavelas carried out a number of studies between 1940 and 1947. One experiment involved the difference between discussion and decision-making in reinforcing people's motivation to raise production levels. Bavelas held informal meetings with two groups of high-producing workers at the Harwood plant. The first group discussed ways to increase its daily production and then voted on the issue of raising its daily production. The group decided to aim for 87 units per day instead of its current level of 75 within a five-day period. It met its goal and later raised the goal to 90 units, which it also achieved. The second group of workers met only to discuss ways to increase production but did not take a vote. Their production improved only slightly over the next few months. Looking at Bavelas' findings, Lewin maintained that they showed that motivation by itself is not enough to produce change. The link between motivation and change is provided by decisions, which often affect long- as well as short-term changes in actual behavior.

Another experiment that Bavelas performed at the Harwood factory under Lewin's supervision reflected Lewis' theory of force fields and his concepts of driving and restraining forces. Bavelas studied the use of pacing cards as a tool that the workers could use for self-management. They were to use the cards to set their own hourly pace as long as they kept at or above the plant's official quota. Lewin's force field theory predicted that a production worker's average output is almost stationary; therefore, one can raise production levels either by adding driving forces to push for higher output (in this case, pressure from management) or weakening the restraining forces that limit the worker's production. Bavelas found that the workers who were given pacing cards raised their average production from 67 units per day to 82 and remained at that level, whereas a control group of workers who were not given pacing cards did not raise their production level. In short, Bavelas' study showed that production is raised more effectively by weakening restraining forces than by putting workers under pressure that raises their stress levels and is ultimately counterproductive.

The Iowa frustration and regression studies During Lewin's years as a researcher at the Child Welfare Research Station at the University of Iowa, he and his former student Tamara Dembo (who had also left Germany for the United States in the mid-1930s) conducted a series of experiments on the effects of frustration on young children. Dembo's doctoral dissertation had involved the dynamics of anger and frustration. What she discovered during a series of 64 experiments with 27 different subjects confirmed Lewin's hypothesis that anger in a frustrating situation is a product of the subject's total life space at that point rather than of simple failure to reach a goal. Dembo's subjects reacted to the frustrating situations she created in one of three ways: they kept trying to complete the task she had set them, although in roundabout ways; they left the room where the experiment was being conducted; or they lashed out at Dembo verbally or even physically. The experiments that Lewin, Dembo, and a third colleague named Roger Barker conducted at Iowa were designed to take the study of anger and frustration to the next level, namely to discover the effects of frustration on children's intellectual creativity and behavior. Lewin and his colleagues reported on their findings in 1941 in the series of University of Iowa Studies in Child Welfare.

CHRONOLOGY

1890: Lewin born in Germany, now a part of Poland.

1914: Volunteers to serve in World War I.

1917: Wounded in war. Later marries first wife, Maria.

1927: Divorces first wife after son's illness strains family.

1929: Marries second wife, Gertrud.

1933: Moves to United States to escape the rise of Hitler.

1944: Invited to set up research institute at MIT.

1944: Lewin's mother dies in Nazi concentration camp.

1946: Pioneers leadership training.

1947: Dies of heart attack.

The researchers had hypothesized that frustrating the play activities of young children would lead to behavioral regression. Regression is a concept that was first used by Freud to describe a return from later to earlier stages of personality organization. For example, parents frequently note that a first-born child regresses to babyish behavior when a newborn arrives in the

BIOGRAPHY:

Fritz Heider

Fritz Heider (1896–1988) was a social psychologist best known for his book The Psychology of Interpersonal Relations, first published in 1958. Heider grew up in Vienna and received his Ph.D. from the University of Graz in Austria before coming to the Psychological Institute at the University of Berlin. There he met Kurt Lewin and formed a friendship with him that lasted until Lewin's death.

Heider left Germany for the United States in 1930 to accept a research position at the Clarke School for the Deaf in Northampton, Massachusetts. He fell in love with Grace Moore, a fellow researcher at Clarke, and married her in December 1930. The Heiders had three sons during their years in Northampton; they also provided Kurt and Gertrud Lewin with a place to stay during the Lewins' first months in the United States. In 1947 the Heiders left Massachusetts for Kansas, where Fritz had been appointed a full professor at the University of Kansas. He remained at Kansas until his retirement in the 1960s, although he continued to do research and work on the notebooks that he had kept throughout his career. The notebooks were published in six volumes shortly before his death in 1988. Heider was honored by the American Psychological Association in 1965, when he received the APA's Distinguished Scientific Contribution Award.

The two concepts most often associated with Heider's work are attribution theory and balance theory. Attribution theory is concerned with the ways in which people explain the causes of other people's behavior, and the reasons for their choice of explanations. Heider distinguished two types of attribution, external and internal. In external (or impersonal) attribution, an observer explains an event or action in terms of such impersonal forces as the weather or similar factors. For example, a baseball fan might interpret a player's falling down in the outfield as the result of heavy rain the night before creating a slippery playing surface. In internal, or personal, attribution, the observer explains behavior as caused by internal factors that make the other person responsible for the behavior. In the case of the outfielder, the fan might attribute the fall to the player's intention (he meant to fall) as well as to his disposition (he's stupid, lazy, stays out too late the night before a game, etc.). What Heider means by a disposition is a "relatively unchanging underlying condition" that allows a person to "predict and control" events in the real world by referring "transient and variable behavior" to these unchanging conditions. Heider thought that people tend to overemphasize dispositions in judging the behavior of others and to discount any external factors involved; he called this tendency attributional bias.

Heider's balance theory, also known as P-O-X theory, is an attempt to explain the fact that people tend to seek balance (whether positive or negative) in their relationships. The letters refer to three points of a triangle formed by a person (P), another person (O), and an object (X). The triangle includes what Heider called relations of sentiment (liking or disliking) as well as unit relations (relationships to other people or objects). An example of balance theory would be a person (P) who has a friend (O) that he likes very much. O shows up for a get-together wearing the ugliest outfit (X) that P has ever seen. This situation creates an imbalance between P's feelings for the friend (positive) and P's opinion of O's clothing (negative). Heider predicts that P will convince himself that his feelings about O's clothes are positive too—he might tell himself that "she has a unique sense of style" in order to restore balance. An example of negative balance would be P's dislike of a neighbor (O)'s dog (X) because P dislikes the dog's owner.

household, demanding to drink from a bottle again, crying and whining, refusing to take naps, etc. Psychiatrists studying shell-shocked veterans of World War I in the 1920s also observed that these emotionally damaged adults often regressed to attitudes and behaviors more characteristic of teenagers. In the Iowa study, Lewin, Dembo, and Barker collected a group of 30 children between two and six years of age. The first phase of this experiment did not involve frustrating the child, who was led alone into a room with play materials while the researcher sat at a desk and made notes. After the child had been playing for 30 minutes, the researcher opened a screen that had closed off half the room, revealing a set of new and exciting toys that the child was encouraged to enjoy. This part of the experiment was intended to create eventual frustration by setting up a desirable goal that the child could be prevented from reaching in the second phase.

After the child had become absorbed with the new toys, the researcher interrupted the play and led the child back to the first part of the room. The new play area was then sealed off with the screen and fastened with a padlock. The child could not reach the new toys even though he could still see them. This situation brought out two types of behaviors—playing with the old toys in the first part of the room and trying to reach the new toys behind the screen. The researchers compared the creativity of the children's play before and after frustration as well as their actual behavior. In the frustration phase of the experiment, the children spent an average of 35% of their time trying to get to the toys behind the barrier or to leave the room. The quality of their play with the old toys was much less creative and constructive than it had been during the first phase. In addition, the children's behavior regressed to a startling degree; some of the five-year-old children regressed to the behavior of three-year-olds, including thumbsucking and general restlessness. Some children even kicked, hit, or broke objects in the study room. Lewin and his colleagues found that the degree of intellectual regression in the children was directly correlated with the intensity of frustration. In addition, there was a marked change in the nature of the children's behavior toward the researcher during the frustration phase of the experiment—a 30% rise in hostile acts and a 34% drop in friendly actions.

In addition to the study that Lewin coauthored with Barker and Dembo, he published another paper in 1941 on "Regression, Retrogression, and Development," in which he proposed that the Iowa research and other studies of regression could serve to shed light on normal patterns of human development.

Our knowledge of the factors determining [normal] development, its dynamics and laws, is extremely meager. Regression can be said to be a negative development.... Therefore, the indirect way of studying the dynamics of development by studying regression may prove to be fruitful for the whole theory.

Relevance to modern readers

Even though Lewin is usually classified as a social psychologist, he contributed to so many different areas within psychology that anyone interested in the field is likely to encounter his influence even when his name is not mentioned. The entire specialty of organizational management is indebted to Lewin's work, as well as technical action research and leadership training programs. Even people who have never studied psychology have been exposed to Lewin's theories if they have ever undergone sensitivity training in their workplace or have participated in team-building programs. Anyone who has been involved in encounter groups or similar programs associated with the human potential movement has also been affected indirectly by Lewin's ideas. Although Lewin's theory of personality has not been as influential over the long term as his work in group dynamics, his concept of tension systems and of human behavior as goal-oriented has stimulated countless research projects in the areas of motivation and aspiration—subjects that were once considered off-limits to scientific investigation. Lastly, anyone who studies psychology in the hope or expectation of making a difference in the world around them has Lewin as a forbearer and a model.

BIBLIOGRAPHY

Sources

Barker, Roger, Tamara Dembo, and Kurt Lewin. "Frustration and Regression." University of Iowa Studies in Child Welfare 18 (1941): 1–43.

Bavelas, Alex, and Kurt Lewin. "The Solution of a Chronic Conflict in a Factory." In Proceedings of the Second Brief Psychotherapy Council. Chicago: Institute for Psychoanalysis, 1944.

Bavelas, Alex, and Kurt Lewin. "Training in Democratic Leadership." Journal of Abnormal and Social Psychology 37 (1942): 115–19.

Darwin, John. Action Research: Theory, Practice and Trade Union Involvement. Sheffield Business School Working Paper No. 99/06. Sheffield, UK: Sheffield Business School, 1999.

Goffman, Erving. Stigma: Notes on the Management of Spoiled Identity. New York: Simon & Schuster, 1963.

Hall, Calvin S., and Gardner Lindzey. Theories of Personality, 2nd ed. New York: John Wiley & Sons, Inc., 1970.

Heider, Fritz. "Attitudes and Cognitive Organization." Journal of Psychology 21 (1946): 107–12.

Heider, Fritz. The Psychology of Interpersonal Relations. New York: John Wiley&Sons, Inc., 1958.

Lewin, Kurt. "Action Research and Minority Problems." Journal of Social Issues 2 (1946): 34–46.

Lewin, Kurt. "Behavior and Development as a Function of the Total Situation." In L. Carmichael, ed., Manual of Child Psychology. New York: John Wiley and Sons, 1946.

Lewin, Kurt. "Bringing Up the Jewish Child." Menorah Journal 28 (1940): 29–45.

Lewin, Kurt. "Constructs in Field Theory." University of Iowa Studies in Child Welfare 20 (1944): 1–29.

Lewin, Kurt. "Cultural Reconstruction." Journal of Abnormal and Social Psychology 38 (1943): 166–73.

Lewin, Kurt. "Defining the 'Field at a Given Time.'" Psychological Review 50 (1943): 292–310.

Lewin, Kurt. "Experiments in Social Space." Harvard Educational Review 9 (1939): 21–32.

Lewin, Kurt. "Forces Behind Food Habits and Methods of Change." Bulletin of the National Research Council 108 (1943): 35–65.

Lewin, Kurt. "Formalization and Progress in Psychology." University of Iowa Studies in Child Welfare 16 (1940): 7–42.

Lewin, Kurt. "Frontiers in Group Dynamics." Human Relations 1 (1947): 2–38.

Lewin, Kurt. "On the Structure of the Mind." Vorsatz, Wille und Bedurfnis. Berlin: Springer Verlag, 1926.

Lewin, Kurt. "Personal Adjustment and Group Belongingness." Jewish Social Service Quarterly 17 (1941): 362–66.

Lewin, Kurt. "Regression, Retrogression, and Development." University of Iowa Studies in Child Welfare 18 (1941): 1–43.

Lewin, Kurt. "Self-Hatred Among Jews." Contemporary Jewish Record 4 (1941): 219–32.

Lewin, Kurt. "Some Social-Psychological Differences Between the United States and Germany." Character and Personality 4 (1936): 265–93.

Lewin, Kurt. "When Facing Danger." Jewish Frontier, September 1939.

Lewin, Kurt, and Paul Grabbe. "Conduct, Knowledge, and Acceptance of New Values." Journal of Social Issues 1 (1945): 53–63.

Lewin, Kurt, Ronald Lippitt, and Ralph K. White. "Patterns of Aggressive Behavior in Experimentally Created 'Social Climates.'" Journal of Social Psychology 10 (1939): 271–99.

Lippitt, Ronald, and Kurt Lewin. "An Experimental Approach to the Study of Autocracy and Democracy: A Preliminary Note." Sociometry 1 (1938): 292–300.

Lippitt, Ronald, Ralph White, and Kurt Lewin. "Patterns of Aggressive Behavior in Experimentally Created Social Climates." Journal of Social Psychology 10 (1939): 271–99.

Marrow, Alfred J. The Practical Theorist: The Life and Work of Kurt Lewin. Annapolis, MD: BDR Learning Products, Inc., 1984.

Potter, Steve. "A Social History of the T-Group." Nurturing Potential 8 (2003). http://www.nurturingpotential.net/Issue8/TGroup.htm.

Rose, Kenneth H. "Leading Change: A Model by John Kotter." ESI Horizons Newsletter February 2002, 1–5.

Schein, Edgar H. Kurt Lewin's Field Theory in the Field and in the Classroom. Notes Toward a Model of Managed Learning. Society for Organizational Learning Working Paper 10.006. Cambridge, MA: Society for Organizational Learning, 1995. http://www.solonline.org/res/wp/10006.html.

Schwartz, Tony. "Nurturing the Human Potential." What Really Matters: Searching for Wisdom in America. New York: Bantam Books, 1996.

Shaw, Robert B., David A. Nadler, and Elise A. Walton. Discontinuous Change: Leading Organizational Transformation. San Francisco, CA: Jossey-Bass Publishers, 1994.

Smith, Mark K. "Kurt Lewin, Groups, Experiential Learning and Action Research." Encyclopedia of Informal Education.http://www.infed.org/thinkers/et-lewin.htm.

Stout, Martha, Ph.D. the Myth of Sanity: Tales of Multiple Personality in Everyday Life. New York: Penguin Putnam, Inc., 2001.

Further readings

Gold, Martin, ed. The Complete Social Scientist: A Kurt Lewin Reader. Washington, D.C.: American Psychological Association, 1999.

Lewin, Kurt. Field Theory in Social Science: Selected Theoretical Papers, edited by Dorwin Cartwright. New York: Harper and Brothers, 1951.

Lewin, Kurt. Resolving Social Conflicts: Selected Papers on Group Dynamics, edited by Gertrud W. Lewin. New York: Harper and Row Publishers, 1948.

Marrow, Alfred J. The Practical Theorist: The Life and Work of Kurt Lewin. Annapolis, MD: BDR Learning Products, Inc., 1984.

Smith, Mark K. "Kurt Lewin, Groups, Experiential Learning and Action Research." Encyclopedia of Informal Education.http://www.infed.org/thinkers/et-lewin.htm.

LEWIN, KURT

(b. Mogilno [present-day Poland], 9 September 1890; d. Newtonville, Massachusetts, 11 February 1947),

psychology, social science, philosophy of science, psychological field theory, topological psychology, group dynamics.

Lewin was the creator of psychological field theory, a pioneer of action research in psychological social science, and a founder of group dynamics. He combined thinking from psychology and philosophy of science throughout his career. His aims were to link theoretical insight with empirical research in the study of motivation, child development, and social behavior, as well as to humanize the workplace and the school with the help of social science. To him these tasks were not opposed; as he often said, nothing is as practical as a good theory.

Lewin was born in Mogilno (now Poland), which was then in the Prussian province of Posen. He was the second child and eldest son of a Jewish family, and knew Yiddish and Hebrew as well as German. His father owned a small general store and a farm outside the town. He was sent to Gymnasium in Breslau and studied medicine briefly in Freiburg im Breisgau before transferring to Berlin, where he studied with the philosopher and psychologist Carl Stumpf and the neo-Kantian philosophers of science Ernst Cassirer and Alois Riehl. He received his doctorate in 1916, while on leave from military service during World War I, and earned the right to teach (Habilitation) in Berlin in 1921. From that time until he resigned for political reasons in 1933, he was Dozent and senior assistant (Oberassistent) in the department of applied psychology at the Psychological Institute of the University of Berlin; he received the title of associate professor in 1927. He married Maria Landsberg in 1917 and had two children with her; after they divorced he married Gertrude Weiss in 1929 and had two children with her. His career after 1933 will be detailed below.

Philosophy of Science . In the 1920s Lewin elaborated a comparative theory of science. Instead of establishing ideal norms for the sciences and humanities according to their subject matter, he based his approach on the concepts scientists actually construct. He was inspired to do this by Cassirer’s comparative and historical treatment of scientific concepts in Substance and Function (1910). His first and most extensive attempt to realize this program was a book on the concept of time series in physics and biology published in 1922. For Lewin, when physicists refer to a particle of matter persisting in a series of instants, this constituted as much a “genetic” (meaning a temporal) series as a reference to the path of energy from a lump of coal to a power plant and thence to a light bulb. In both cases what he called “genidentity” (Genidenität) is attributed to the object in question. Correspondingly, when an egg develops into a chicken, biologists speak of the life history of a single organism, even though egg and chicken might have no molecules in common, except perhaps in the germ cell; moreover, in evolutionary theory biologists construct historical series of species linked by descent, even though there may be no proven material linkages between them. Thus, in physics and biology entities defined as existing continuously over time differ according to the point of view required by the scientific task at hand. In the 1920s Lewin extended this pluralistic, pragmatic analysis to other disciplines, but chose not to publish the resulting texts.

Lewin was in contact with the founders of the logical empiricist movement, particularly Hans Reichenbach, with whom he had been involved in the Socialist youth movement before World War I. When Reichenbach organized the Society for Scientific Philosophy in Berlin in the late 1920s, Lewin participated actively. He shared the logical empiricists’ interest in illuminating the conceptual foundations of science by examining actual scientific concepts, but rejected Rudolf Carnap’s and Otto Neurath’s call for a unified science based on physical language.

Lewin presented his view of psychology’s place in his philosophy of science in two essays: “Law and Experiment in Psychology” (1927), and a paper on the transition from “Aristotelian” to “Galilean” thinking in psychology (1931), which first appeared in the journal Erkenntnis, the organ of the logical empiricist movement. In the 1927 paper he noted that what appears to be a unitary behavioral event may be the result of multiple psychological processes. Though this statement appears to deny the possibility of causal explanation in psychology, it could also be true of physical events and processes. A rolling ball, for example, appears to be a single series of events, yet a complete physical analysis shows it to be the product of multiple forces in interaction. A child’s behavior in a given situation can also be seen as a product of interacting forces. Thus, in Lewin’s view, it is possible to derive causal laws for psychology without reducing psychical phenomena to physical events. Instead, he posited “event types” (Geschehenstypen) as the appropriate explanatory objects for psychology, and hoped that laws for such “event types” would eliminate factors such as previous experience or heredity from psychological explanations.

In the 1931 paper, Lewin opposed the idea that psychology is or ought to be limited to statistical laws. He called such claims “Aristotelean,” because they referred to typological categories such as “the obstreperous three-year-old,” or to specific populations, such as one-year-old children in Vienna and New York in 1928. Modern physics, in contrast, derives universal mathematical laws from concrete, albeit ideal cases. Lewin proposed to create a “Galilean” or dynamic psychology, in which, instead of computing statistical averages from as many given cases as possible, researchers would recreate and analyze ideal-typical person-environment interactions in the laboratory. For him analysis of such interactions was a necessary basis for deriving formal, ultimately mathematical, descriptions of their dynamics. He understood this procedure to be analogous to the way in which Galileo had deduced the laws of free fall and projectile motion from mathematically derived “pure cases.”

Research and Theory on Volition and Motivation . Lewin’s early research challenged associationist theories of volition. Narziss Ach had suggested in 1910 that “determining tendencies” stimulated by an experimenter’s instruction inhibit subjects’ ability to recall associative connections they had already learned; the resulting delay in carrying out the instruction would thus be a measure of will. In his dissertation (published 1917) Lewin set out to improve this measure by asking observers to learn lengthy series of meaningless syllables, then instructing them either to reverse or rhyme the syllables. The prediction was that they would either take longer to complete the second task or give wrong answers. To his surprise, there was generally no inhibitive delay, and only a few errors. In further studies, using different instructions (for example, to rhyme syllables in a specific way), he found that subjects made few errors even with only a few repetitions during the training period. Lewin concluded that Ach’s associationist view of will was untenable, because the predicted effects failed to occur even under optimal conditions, and decided that more work was needed on the relation of motivation and volition.

Lewin’s subsequent studies of motivation and action during the 1920s combined affiliation with and independence from the Berlin school of Gestalt theory, whose leading thinkers Wolfgang Köhler and Max Wertheimer were Lewin’s colleagues at the time. In papers titled “Preliminary Remarks on the Structure of the Mind” (author’s translation) and “Intention, Will, and Need” (both 1926), Lewin accepted the Gestalt theorists’ claim that actions, like acts of perception, are structured wholes (his term was “action wholes”), but he enriched their conception of behavior in two respects. First, he focused on the way situations appear to the actor at a given time, which he called their “psychological reality”; he suggested, further, that the psychical person is itself a complex, “layered” whole. The needs that influence a person’s interaction with the (perceived) environment can come from more superficial or deeper layers of the self. Thus, the totality of forces present in the psychical field at a given time controls the direction of action; and this totality is not limited to perceived objects and their relations to an actor, but can include objects and needs of which the actor is not conscious.

Lewin did not call this approach “field theory” at this time, but the expression “field forces” is ubiquitous in his German work. A frequently cited example of the impact of such forces is what he called the “demand character” of objects. The roots of this concept are already visible in an essay called “Kriegslandschaft” (1917; Warscape), written while he was at the front. That a house might appear to someone as a source of firewood, for example, would be barbarous in peacetime, but quite normal and maybe even necessary in war. The example he used in 1926 was a “peace thing”: a mailbox has a different relation to me when I have a letter in my hand than when I do not. In the former case, the mailbox seems almost to jump out of the environment and announce its presence.

Lewin attributed such phenomena to what he called “quasi-needs,” contending that objects related to them exert greater psychological “force” at particular times than at others. To account for these he suggested that “tension systems” emerge in specific “regions” of the self; these function in the same way as the tensions caused by real needs, transforming the psychical environment in accordance with a person’s current intentions. The satisfaction of such needs reestablishes personal equilibrium at a lower level of tension. Of course, the “tension” in such systems is not directly measurable, as is the tension in a coiled spring.

Lewin’s students in Berlin elaborated these ideas in empirical studies published in the journal Psychologische Forschung, in a series he edited entitled “Studies on the Psychology of Action and Emotion” (author’s translation). Among the studies were Bluma Zeigarnik’s investigation of memory for completed and uncompleted tasks (1927), the work of Anitra Karsten on “psychical satiation” in repetitive tasks (1928), Tamara Dembo’s study of the dynamics of anger (1931), and Ferdinand Hoppe’s work on the role of “level of aspiration” in task completion. These studies contained richly detailed descriptions of motivated actions, achievement, and task interruption, derived with the help of an interactive methodology of Lewin’s invention. Dembo’s experimental design, for example, involved an actual struggle between subject and experimenter, who deliberately frustrated subjects’ efforts to complete the assigned task, then prevented them from leaving the room.

Psychology in Practice . Lewin’s choice of topics clearly indicated his desire to connect scientific psychology with practical issues. He expressed that wish as early as 1920, in an essay entitled “The Socialization of the Taylor System” (author’s translation), published just after the abortive German revolution in a series entitled “Practical Socialism” (author’s translation), edited by his friend and independent Marxist thinker Karl Korsch. Lewin did not object in principle to Taylorism’s attempt to discover quantitative laws of performance that could rationalize production and thus increase output. Instead he criticized capitalism’s use of that effort to maximize profit rather than workers’ well-being. Under socialism, he argued, workers could be assigned to jobs according to their abilities in a cooperative effort involving management, workers, and psychologists; thus both productivity and job satisfaction would be enhanced.

Humanizing the workplace and the school remained Lewin’s aim throughout the 1920s and beyond, and his choice of basic research topics was clearly related to this purpose. In a 1928 essay, for example, Lewin suggested on the basis of Karsten’s study of “satiation” that the psychological meaningfulness of a task to a worker can vary significantly even if productivity in output remains the same. This can have significant impact on the quality of performance, and even on physical fatigue. Thus, monotonous factory or school work alone does not cause psychological satiation; the decisive difference is the involvement of the person’s self or ego. In the same year, in a paper on the textile industry published together with applied psychologist Hans Rupp, Lewin elaborated an analysis of work as a process, an “action whole” (Geschehensganze) that constitutes man and machine as a dynamic unity. In his view, it was important to consider the work process as a whole and not only to measure results or the times of individual motions of workers, because the purpose is to reshape that process itself.

At this stage, Lewin confined himself to the behavior of individuals in simply structured environments. This was true also of the film of a small child’s problem-solving behavior, with which he introduced himself to American colleagues at the International Congress of Psychology in New Haven, Connecticut, in 1929. However, he always made it clear that other people are important parts of such environments. In the late 1920s and the early 1930s, he extended his thinking to pedagogy, speaking, among other things, of the importance of the “social atmosphere” of a school for educational success. He also described the behavior of children in conflict situations in ways that included relations with significant other people such as parents and teachers within the (subjective) field of children’s action. However, he did not investigate social psychological questions or have the idea of working with groups as units before leaving Germany.

After 1933 . Because Lewin had served at the front during World War I, he was nominally exempt from the provisions of the Nazi civil service law of 7 April 1933, which mandated the dismissal of persons of Jewish descent from state employment. His institute head, the Gestalt psychologist Wolfgang Köhler, wished to retain him in Berlin, but Lewin recognized the danger for Jews who remained in Germany. In a moving letter to Köhler dated 20 May 1933, which he never sent but which was discovered in his papers after his death, he wrote, “Everything within me rebels against the idea of leaving Germany despite all logical arguments,” and yet,

The actual loss of civil rights of the Jews has not abated, (but) is increasing daily and will no doubt be carried out completely in the peculiarly systematic German way, whether slowly and methodically, or in periodic waves … I cannot imagine how a Jew is supposed to live a life in Germany at the present time that does justice to even the most primitive demands of truthfulness.

Shortly after he left his position in Berlin, Lewin received a stipend at Cornell University, where he worked on children’s eating habits with support from the Emergency Committee in Aid of Displaced Foreign Scholars and the Rockefeller Foundation. Lawrence K. Frank, a foundation official who had met Lewin in Berlin and had been impressed by his experiments with children, then obtained a new grant in 1935 that sent Lewin to the Child Welfare Research Station at the University of Iowa. There he soon received a tenured appointment, rose to the rank of full professor in 1939, and remained until 1944. Both the Cornell center and the Iowa station were participants in a large-scale research program in child development that had been maintained with Rockefeller funding since the mid-1920s.

Because of his rapid integration into this network, Lewin refused the offer of a professorship from the Hebrew University in Jerusalem, which, as a Zionist, he would have preferred to accept. For this position he devised an ambitious research program, including, for example, studies of the relations between Jews and Arabs in Palestine. But the Jerusalem offer included no laboratory facilities, and Lewin’s efforts to raise money for these from private donors failed.

Nonetheless, Lewin took up the problems of minorities soon after his emigration. In a 1935 paper on social-psychological problems of a minority group, the topic was clearly the Jews. Here, Lewin extended the concept of “life space,” which he had already employed before 1933 to describe the subjective location of human-environment interactions, to human-human relationships under the heading “social space.” He argued that precisely Jews who wished to assimilate to a predominant culture had difficulty in forming clear identities, because their location on the boundary between groups did not allow them to develop a feeling of belonging to either group. Roots of the concept of “marginal man,” later articulated by Seymour Martin Lipset and others, can be seen here.

After moving to Iowa, Lewin took up the topic of cultural differences in education. This issue had obvious relevance in a research center for child welfare, but biographical factors plainly contributed to the choice: His younger children were reaching school age and the international situation literally demanded such comparisons. In this context, what he called the “range of free movement” became the fundamental feature of educational systems. The presence of hierarchical structures even in the “democratic” educational style of the United States, and the reliance of American teachers on externally mandated teaching plans and techniques gave American children, in Lewin’s opinion, the support they needed to act independently in a heterogeneous social system, while rigidity and strict obedience were the educational norms in the comparatively homogeneous German social system.

From such considerations, and also on the basis of conversations that Lewin had with American collaborators in Iowa, came the studies of “democratic” and “authoritarian” leadership styles in children’s play groups that made Lewin famous in America. In the “authoritarian” group both the task—making theater masks—and the way it was to be accomplished were defined step by step by the group leader, who intervened only to criticize the children’s work. In the “democratic” group, the leader participated as a fellow group member, for example in decisions about how and with what materials to make the masks; he was allowed to give technical advice, but only when asked and then only in the form of presenting alternatives from which the group then chose.

In this work Lewin transferred the approach he had called “Galilean” in the early 1930s—the construction of ideal-typical person-environment interactions—to the behavior of groups. The “Lewin, Lippitt, and White” study, as it came to be known, acquired an almost mystical aura as the first group experiment in the history of social psychology. To visualize their approach, Lewin and his collaborators made a demonstration film that presented the behavior of the children’s groups in often amusing scenes and was soon much in demand. The ideological resonances of this research were obvious in the late 1930s; one reason for the rapid success of the Iowa group’s work was the support it seemed to provide for the hope that “democratic” leadership is indeed possible.

The politically progressive psychologists who founded the Society for the Psychological Study of Social Issues in 1936 shared this hope. Moved in part by impatience with their discipline’s slow response to the problems of the Depression, the organization’s members advocated social research for social change, if necessary by abandoning professional objectivity and distancing methodologies. Lewin was among the founders, and was elected president of the society in 1942–1943.

Building on this foundation, Lewin developed an ambitious program in the late 1930s and 1940s that he called “action research,” to be conducted not in laboratories but in factories and communities. Early work along these lines at the Harwood Manufacturing Corporation reflected the roots of this approach in Lewin’s Taylorism study of 1920, but he soon applied it to minority group issues as well. That program, organized within the framework of a Commission on Community Interrelations (CCI) and funded largely by the politically liberal American Jewish Congress, aimed both to study the social psychology of racism and anti-Semitism and at the same time to work toward changing racist and ethnically prejudiced social relations by deriving concrete practical guidelines from observations of group behavior and reflections on that behavior by the group members themselves. In a 1946 paper Lewin himself described all this as “research for social engineering.”

By this time, Lewin had already moved from Iowa to the East Coast. Beginning with a visiting professorship at Harvard in 1939–1940, he expanded his contacts through work on morale research during World War II, including a programmatic essay on transforming Germany after Allied victory. In 1944 he accepted a professorship established for him at the Massachusetts Institute of Technology (MIT), where he founded an interdisciplinary Research Center for Group Dynamics.

Lewin never gave up hope of unifying theoretical and applied psychology. The means was to be topology, with the aid of which he hoped to achieve a mathematically rigorous representation of psychological dynamics. By the late 1920s, he had begun to transform this abstruse branch of mathematics into a device for the formal representation of psychological field forces and concrete psychological situations as well as the structure and internal dynamics of personality. In Principles of Topological Psychology (1936) he elaborated this approach in detail, with the hope of moving eventually to a process—rather than a performance-oriented concept of psychological measurement.

Impact . After Lewin died from a heart attack in 1947, at the age of fifty-seven, his prestige reached its high point. Edward Tolman went so far as to call him the most important thinker in the history of psychology after Sigmund Freud. Many Lewinian terms, including “level of aspiration,” “life space,” and “marginal affiliation,” and slogans such as “nothing is as practical as a good theory” entered the vocabulary of American psychology, and later returned to Europe via translations into German and other languages. The Research Center for Group Dynamics, which moved from MIT to the University of Michigan at Ann Arbor shortly after his death, still existed in the early twenty-first century; Lewin’s reputation as a founder of experimental social psychology seems secure. Nonetheless, his experiments with “authoritarian” and “democratic” groups, though greatly admired, did not become exemplars for research design. Rather than study groups as wholes, mainstream social psychologists generally examine the influence of groups on the behavior of individuals. However, some of Lewin’s collaborators were instrumental in establishing the T-group and group dynamics movements in the 1950s, and others were among the founders of the approach called “ecological psychology” in the 1960s.

Lewin’s idea of a “topological and vector psychology” has come to be regarded as a blind alley. In the 1930s few psychologists outside Lewin’s immediate circle understood what he was talking about, and rivals willingly seized on disparaging remarks by mathematicians about his unsophisticated use of topology. Seen in historical context, his “Galilean” research program paralleled and competed with Yale psychologist Clark Hull’s equally ambitious, and disappointing, effort to derive general laws of behavior deductively in a manner allegedly analogous to Isaac Newton’s system of the natural world.

In the 1970s and 1980s Lewin’s program for making psychology an agent of social change was sharply criticized from the left as a reformist project that would not change fundamental power relations. Since the 1990s action research has experienced a comeback as a results-oriented approach to understanding political conflict.

Lewin’s fecund metaphors and brilliant individual insights, as well as his ability to inspire talented researchers, made him a success in Berlin, in the United States, and then internationally. He established an independent research base in America, but it was his cogent criticism of predominant styles of thought and practice in American psychology and his effort to develop concrete alternatives that gained him a hearing. At the same time, his support for U.S. democracy and his optimism about the practical potential of social science impressed the progressive segment of his discipline. His early work in the philosophy of science has never been translated into English and thus remains largely unknown outside Germany. For historians of science, his career exemplifies the deep connection of modern social science with social practice and also shows how a Jewish scientist created new science after reflecting on his own persecution under Nazism.

BIBLIOGRAPHY

A collection called the Kurt Lewin Papers is located in Ohio at the Archives of the History of American Psychology, University of Akron. This consists primarily of materials used by Alfred Marrow to prepare his biography of Lewin (see below). Other collections of Lewin manuscripts and correspondence are located at the Institute for History of Modern Psychology in Passau, Germany, and the Distance University (Fernuniversität) in Hagen, Germany.

WORKS BY LEWIN

Die Sozialisierung des Taylorsystems: Eine grundsätzliche Untersuchung zur Arbeits- und Berufspsychologie. Praktischer Sozialismus 4. Berlin: Weltkreisverlag, 1920.

Der Begriff der Genese in Physik, Biologie und Entwicklungsgeschichte: Eine Untersuchung zur vergleichenden Wissenschaftslehre. Berlin: Springer-Verlag, 1922. Reprinted in Kurt-Lewin-Werkausgabe, vol. 2, pp. 47–318.

Gesetz und Experiment in der Psychologie. Berlin: Weltkreis-verlag, 1927. Reprinted in Kurt-Lewin-Werkausgabe, vol. 1, pp. 279–320.

Die Entwicklung der experimentellen Willenspsychologie und die Psychotherapie. Leipzig: Hirzel, 1928.

Die psychologische Situation bei Lohn und Strafe. Leipzig: Hirzel, 1931. Reprinted in Kurt-Lewin-Werkausgabe, vol. 6, pp. 113–168.

A Dynamic Theory of Personality: Selected Papers. Translated by Donald K. Adams and Karl E. Zener. New York: McGraw-Hill, 1935.

Principles of Topological Psychology. New York: McGraw-Hill, 1936.

Experimental Studies in the Social Climates of Groups, Parts I and II. 1938. This film is available in several locations. The original is located at the Herbert Hoover Presidential Library and Museum, West Branch, Iowa. Restored copies are available at the University Archives, University of Iowa, Iowa City. An unrestored copy is located at the Archives of the History of American Psychology, University of Akron, Ohio.

With Ronald Lippitt and Robert K. White. “Patterns of Aggressive Behavior in Experimentally Created ‘Social Climates.’” Journal of Social Psychology 10 (1939): 271–299.

Resolving Social Conflicts, Selected Papers on Group Dynamics [1935–1946]. Edited by Gertrude Weiss Lewin. New York: Harper, 1948.

Field Theory and Social Science: Selected Theoretical Papers. Edited by Dorwin Cartwright. New York: Harper, 1951.

Kurt-Lewin-Werkausgabe. Edited by Carl-Friedrich Graumann. Vols. 1, 2, 4, and 6. Stuttgart: Klett-Cotta; Bern: Huber, 1981–1982. Four of eight projected volumes published.

“Everything within Me Rebels: A Letter from Kurt Lewin to Wolfgang Köhler.” Translated by Gabriele Wickert and Miriam Lewin. Journal of Social Issues 42 (1986): 40–47.

The Complete Social Scientist: A Kurt Lewin Reader. Edited by Martin Gold. Washington, DC: American Psychological Association, 1999.

OTHER SOURCES

Ash, Mitchell G. Gestalt Psychology in German Culture, 1890–1967: Holism and the Quest for Objectivity. Cambridge, U.K.: Cambridge University Press, 1995. See especially chapter 16.

———. “Cultural Contexts and Scientific Change in Psychology: Kurt Lewin in Iowa.” American Psychologist 47 (1992): 198–207. Reprinted in Evolving Perspectives on the History of Psychology, edited by Wade E. Pickren and Donald A. Dewsbury. Washington, DC: American Psychological Association, 2001.

———. “Learning from Persecution: Émigré Jewish Social Scientists’ Studies of Authoritarianism and Anti-Semitism after 1933.” In Jüdische Welten, edited by Beate Meyer and Marion Kaplan. Juden in Deutschland vom 18. Jahrhundert bis in die Gegenwart. Göttingen: Wallstein, 2005.

Back, Kurt. Beyond Words: The Story of Sensitivity Training and the Encounter Movement. Baltimore, MD: Penguin, 1973.

Bargal, David. “Kurt Lewin and the First Attempts to Establish a Department of Psychology at the Hebrew University.” Minerva 36 (1998): 49–68.

———. “Personal and Intellectual Influences Leading to Lewin’s Paradigm of Action Research.” Action Research 4, no. 4 (2006): 367–388.

Cravens, Hamilton. Before Head Start: The Iowa Station and America’s Children. Chapel Hill: University of North Carolina Press, 1993.

Danziger, Kurt. Constructing the Subject: Historical Origins of Psychological Research. Cambridge, U.K.: Cambridge University Press, 1990.

———. “The Project of an Experimental Social Psychology: Historical Perspectives.” Science in Context 5 (1992): 309–328.

———. “Making Social Psychology Experimental: A Conceptual History, 1920–1970.” Journal of the History of the Behavioral Sciences 36 (2000): 329–347.

De Rivera, Joseph, ed. Field Theory as Human-Science: Contributions of Lewin’s Berlin Group. New York: Gardner, 1976.

Habermas, Tilmann. “Eine nicht ganz zufällige Begegnung: Kurt Lewins Feldtheorie und Siegfried Bernfelds Psychoanalyse im Berlin der späten 20er Jahre.” Zeitschrift für Psychologie 209 (2001): 416–431.

Journal of Social Issues 42, nos. 1–2 (1986). Special issues on Kurt Lewin.

Lück, Helmut E. Kurt Lewin: Eine Einführung in sein Werk. Weinheim: Beltz, 2001.

Marrow, Alfred. The Practical Theorist: The Life and Work of Kurt Lewin. New York: Basic, 1969. Appendices include an incomplete biography of Lewin’s works; summaries of the Berlin experiments; members of the “Topology Group” (1935); studies done under Lewin’s direction in Iowa; CCI publications; and publications of the Research Center for Group Dynamics, 1945–1950.

Métraux, Alexandre. “Kurt Lewin: Philosopher-Psychologist.” Science in Context 5 (1992): 373–384.

Patnoe, Shelley. A Narrative History of Social Psychology: The Lewin Tradition. Berlin: Springer-Verlag, 1988.

Schönpflug, Wolfgang, ed. Kurt Lewin: Person, Werk, Umfeld: Historische Rekonstruktionen und aktuelle Wertungen aus Anlass seines hundertsten Geburtstags. Vol. 5 of Beiträge zur Geschichte der Psychologie. Frankfurt am Main: Lang, 1992.

Schwermer, Josef. Die experimentelle Willenspsychologie Kurt Lewins. Meisenhein am Glan: Hain, 1966.

Stivers, Eugene H., and Susan A. Wheelan, eds. The Lewin Legacy: Field Theory in Current Practice. New York: Springer-Verlag, 1986.

Tolman, Edward C. “Kurt Lewin (1890–1947).” Psychological Review 55 (1948): 1–4.

Van Elteren, Mel. “Karl Korsch and Lewinian Social Psychology: Failure of a Project.” History of the Human Sciences 5 (1992): 33–61.

Wittmann, Simone. Das Frühwerk Kurt Lewins: Zu den Quellen sozialpsychologischer Ansätze in Feldkonzept und Wissenschaftstheorie. Frankfurt am Main: Lang, 1998.

Mitchell G. Ash

Lewin, Kurt

WORKS BY LEWIN

SUPPLEMENTARY BIBLIOGRAPHY

Kurt Lewin (1890–1947) was born in Mogilno, Prussia. After studying at the universities of Freiburg and Munich, he completed his doctorate in philosophy at the University of Berlin in 1914. He taught in Berlin from 1921 to 1933, at which time he left Germany. In the United States he was a visiting professor at Stanford and at Cornell before becoming professor of child psychology in the Child Welfare Research Station of the State University of Iowa in 1935. In 1945 he left Iowa to found the Research Center for Group Dynamics at the Massachusetts Institute of Technology. He also served as a visiting professor at the University of California in Berkeley and at Harvard.

During his thirty years of scientific work, Lewin’s theoretical interests and the focuses of his research shifted several times. At first he was concerned with the study and analysis of the cognitive processes of learning and perception; with the dynamics of individual motivation and emotion; and with the interpersonal processes of reward and punishment, conflict, and social influence. In his next phase, he conducted and stimulated research on group phenomena such as leadership, social climate, group standards, and values. Finally, he was led to an examination of the social restraints imposed on groups by technology, economics, law, and politics. Although his interests changed and developed, he nevertheless carefully adhered to a central theoretical tenet: that to represent and interpret faithfully the complexity of concrete reality situations requires continual crossing of the traditional boundaries of the social sciences, rather than a progressive narrowing of attention to a limited number of variables.

The theory that requires this interdisciplinary approach to psychological and social reality has at various times been referred to, by Lewin himself and by others, as “dynamic theory,” “topological psychology,” and “field theory.” Field theory was Lewin’s final preference. Briefly stated, it holds that events are determined by forces acting on them in an immediate field rather than by forces acting at a distance. Field theory may be characterized as a method of analyzing causal relations and building scientific constructs, that is, a theory about theory building, or a metatheory. At the same time, Lewin’s field theory is a set of constructs, developed through empirical research, for describing and interpreting psychological and social phenomena.

Field theory as metatheory . The major tenets of field theory as metatheory for social science have been identified by Cartwright (1959, p. 7).

(1) The full empirical reality of human experience and behavior—not just certain abstract aspects that are most accessible or easy to manipulate—must be comprehended in a scientific manner. The observation of behavior in a real-life setting (what has been called naturalistic observation) and phenomenological analysis are procedures that may prevent scientific formalization from focusing on trivial aspects of human behavior.

(2) The language of concepts that is developed must be “two-faced,” providing both a rigorous terminology for describing the behavioral events of the real world and a set of theoretical constructs that can be related to each other logically in the formulation of lawful regularities about the causation of behavioral events.

(3) The concepts must “fit” the nature of psychological phenomena, which they will not do if they are simply borrowed from physical or biological science. Presuppositions about the ultimate unity of science should not be allowed to distort the development of concepts that are intended to describe psychological phenomena (emotions, hopes, fears, illusions) rather than biological or physical processes.

(4) Lewin’s principle of concreteness states that effects “can be produced only by what is ’concrete,’ i.e., by something that has the position of an individual fact which exists at a certain moment” (1936, p. 32). From this important principle Lewin derived several of his basic ideas: that every behavioral event must be viewed as caused by several interdependent features of the total concrete situation of that moment; that the dynamics of a behavioral event cannot be adequately comprehended by the specialized concepts of a particular discipline or scientific specialty, for example, cognition, learning, economics, or political science; that the “life space” or concrete field of all coexisting psychological facts is quite different from the quantified dimensions of that situation; that causation is a contemporary process—“Since neither the past nor the future exists at the present moment it cannot have effects at the present”(ibid., p. 35).

(5) Mathematics provides basic tools for developing a formal systematic theory of psychological processes, but this does not mean that all phenomena can be treated quantitatively. Non-Euclidean geometry seemed to Lewin the most appropriate mathematical tool for treating many empirical aspects of human behavior in terms of psychological space.

(6) Basic research that is generated by the need to develop field theoretical concepts should be of great practical value in the world of action. To Lewin this meant that there “is nothing as practical as a good theory.” He demonstrated this again and again in his own contributions to the understanding of many critical social problems, such as autocracy, self-hatred, scapegoating, intergroup conflict, industrial inefficiency, conservative food habits, and child rearing. [SeePrejudice.]

Experimental research . In his search for a comprehensive conceptual grasp of significant psychological events and processes Lewin instigated and led many research programs, Often they were carried on by his students after he himself had turned his attention to new problems.

His first research sequence began with an experimental critique of the work of Ach (1910) on “associative bonds” in the process of remembering. Lewin moved beyond structural concepts of remembering to such notions as intention to recall and expectation about events. Basic work was done by Ovsiankina (1928) and Zeigarnik (1927), who demonstrated experimentally that the tendency to recall interrupted tasks is stronger than the tendency to recall completed tasks and that there are forces acting toward resuming and completing interrupted activities.

This work on psychological interruption and on the forces acting toward resumption and completion led directly to another program of research that represents an early experimental investigation of motivational concepts. The research sought to discover whether the completion of a task different from the interrupted one can reduce the tendency to resume the interrupted one. In other words, can one task have substitute value for another? Lewin’s students Lissner (1933) and Mahler (1933) demonstrated that tasks of different degrees of similarity and different degrees of reality have different types of substitute value. An important series of studies by Adler (1939), Cartwright (1942), and Sliosberg (1934) further developed this area of inquiry.

Lewin’s interest in the internal dynamics of motivation led him to initiate another series of studies on the psychological process of satiation. Karsten (1928) and other students (Freund 1930; Kounin 1941; Seashore & Bavelas 1942) discovered that the time it takes to become satiated with a task depends on the over-all meaning context of the activity, on ego involvement in the activity, on the physiological state of the person, and on the degree of rigidity of interpersonal psychological systems.

Another important series of studies of motivational dynamics dealt with frustration and regression. Again, Lewin’s plan of research was primarily carried out by others. Dembo’s initial work in Berlin (1931) consisted of careful observational studies of the symptoms of emotional tension as contrasted to the symptoms of task- or problem-solving tension that occurred when subjects were assigned impossible tasks. The symptoms observed included anger, aggression, regression, substitution, and flight from reality. Later studies by Barker, Dembo, and Lewin (1941) and by Wright (1942) established important connections between frustration and intellectual regression as measured by the developmental level of play activity before and after frustration situations.

Dembo (1931) and Hoppe (1931) did valuable research on the concept of level of aspiration, and again other research developed from it. After Jerome Frank, one of Lewin’s students, presented a summary in English of the German research (1935 a; 1935 b), a flood of studies by American investigators followed. The early research indicated that the experience of success or failure depends to a very significant degree upon the person’s aspiration rather than upon some objective standard of performance. There was also clear evidence that the motivation for success or achievement of individuals leads them to set levels of aspiration that do not guarantee easy success. This line of inquiry has been the springboard for much of the current advanced theoretical work on social comparison processes, self-evaluation, and discrepancies between ideal self and actual self.[seeAchievement Motivation.]

The phenomena of decision making and conflict resolution were the focuses of another important series of investigations by Lewin and his students. These inquiries demonstrate the effect on decision making of the strength of the valences of the alternatives, the reality level of the choice situation, the difference in a choice between negative and positive alternatives, and attitudes of cautiousness and risk taking.

As Lewin’s interests changed from individual to social psychology, his approach to decision making and conflict also changed. His famous series of studies of group decision making (1953) demonstrates the influence on individual behavior of participation in group discussions and decisions. Group discussion affects such phenomena as parental behavior, eating habits, and amount of effort on the production line. Later work on patterns of intergroup conflict derived from this work on individual decision making.

As he moved into social psychology, Lewin’s research interests focused on the phenomena of social perception, social values, social influence, cooperation, and competition. In all these areas he instigated important research. His students demonstrated experimentally that the expectation or perception that another person is “warm” or “cold,” high or low in power, or an insider or outsider greatly influences interpersonal attitudes and behavior (Kelley 1950; Pepitone 1950; Thibaut & Riecken 1955).[seePerception, articles onPerson Perceptionand Socialperception.]

His move from Germany to the United States stimulated Lewin’s interest in the comparative analysis of personal values as they relate to cultural differences and social norms. Several of Lewin’s papers ([1935–1946] 1948, pp. 3-68) deal with the development of a definition of values and with approaches to change in cultural values. This was perhaps the beginning of his focus on the theory of planned change and social action, which became increasingly important in the later years of his career. His work on values moved from methodological work on the content of values (as developed in Kalhorn 1944; White 1951) to work on the development of the value of “fairness,” which he conducted by means of experimental situations with children of different ages, and then to an important series of studies on the development and functioning of group standards or group norms. The experimental field studies of the influence of group standards on work output in a factory (Coch & French 1948) and on behavior of residents in a housing project (Festinger et al. 1950) led to a basic theoretical paper in 1947 by Lewin (see in [1939–1947] 1963, pp. 188–237) on the quasi-stationary equilibrium as a tool for conceptual analysis of the field of forces determining behavior in a given social setting and situation. [seeMoral Development.]

Perhaps Lewin’s best-known contributions to social psychology and group dynamics are those focusing on authority and social influence. Initially, a series of children’s groups were studied to see what effect different styles of leadership might have on the social–emotional atmosphere of a group, on its work productivity, and on the personal adaptation of members. There followed basic work on social influence, with laboratory studies of status hierarchy and communications channels; field studies of behavioral contagion and influence structures; and studies of the patterns and bases of influence in military units and in the working relations among the members of professional teams, such as those composed of psychiatrists, clinical psychologists, or social workers. [seeLeadership.]

In the later years of his career, Lewin and his co-workers became interested in the problem of what they called psychological ecology. Thus, in his work on the maintenance and change of food habits (1943), Lewin constructed a theory of social channels and “gatekeepers” to account for the ecological processes by which particular foods reach the table and come in contact with the consumer. He showed that a number of cultural, economic, and technological factors combined to influence this series of decisions. This approach has been greatly developed and extended by Lewin’s student and co-worker Barker, in his series of field studies of the psychological ecology of children and adults in a number of communities and a variety of social settings (Barker & Wright 1954).

Major concepts . In all his work, Lewin maintained an active interplay between the construction of theory and the concrete analysis of human behavior in all its complexity. It is possible here to indicate only briefly some of the concepts that became important in Lewin’s comprehensive conceptual system. Probably the most widely known Lewinian concept is that of psychological life space. This fundamental notion refers to the totality of events or facts that determines the behavior of an individual at a given time. It is related to the basic tenet that causation is a contemporary process, and it has, therefore, created much active controversy in the field of psychotherapy. Defending the importance of this concept, one psychoanalyst (Ezriel 1956, p. 32) has asserted that the unconscious structures the analyst uncovers in working with a patient are active in the present and are not necessarily replicas of past realities and reactions.

The life space includes two major components: the person and the psychological environment. The latter is conceived to be the environment as it exists for the individual. Lewin assumed that an understanding of the interaction between the person and the psychological environment would permit the understanding and prediction of the person’s behavior.

The concepts that Lewin developed to deal with the psychological and social processes of the life space can be classified as structural concepts, having to do with the arrangement and relationship of the parts of the life space, and dynamic concepts, dealing with tendencies toward change or resisting change. The basic structures of the life space are region and boundary, and derived from these are degree of differentiation, centrality, path, and psychological distance. The principal dynamic processes are interdependence, tension, force, field of forces, equilibrium, and power. Lewin also introduced two dimensions of the life space: a vertical dimension of degrees or levels of reality and a horizontal dimension of time perspective. Lewin’s studies demonstrated that psychological processes vary with different levels of reality: the processes involved in assessing facts or expectations are different from those involved in fantasies or wishes. The use of the concept of time perspective was related to Lewin’s field-theoretical stress on the interpretation and prediction of behavior in ahistorical terms.

When he first made contributions to social psychology, Lewin was content to treat the facts of interpersonal relations as social facts in the life space of each individual. For example, the fact of group membership and its implications for behavior then seemed quite satisfactorily represented as regions in the life space of the person. But as he added such new problems as group goals, group decision making, and group problem solving, it became necessary to relate life spaces to one another, that is, to construct a social space or a social field in which social, economic, political, and physical facts have objective, or at least inter-subjective, reality, rather than only individual psychological reality. In some of his final papers ([1939–1947] 1963, pp. 170–237), Lewin was beginning to grapple with the challenging problems of defining social space and social field-theory and of relating these concepts to those of psychological space. He was indicating some of the ways in which the behavioral sciences might go beyond empirical unity to the achievement of conceptual unity.

Social action and social problem solving . Lewin had a deep sensitivity to social problems and a commitment to use his resources as a social scientist to do something about them. Thus, in the early 1940s, he drew a triangle to represent the interdependence of research, training (or education), and action in producing social change. He saw every practical problem as requiring basic conceptual analysis, research, and a “change experiment.” The concept of action-research as a method of planned social change was developed and clarified in the period when he was helping found the Commission on Community Interrelations of the American Jewish Congress and establishing the Research Center for Group Dynamics at MIT.

Lewin may well have been a bit optimistic when he asserted in 1945 that “leading practitioners” in government, agriculture, industry, education, and community life seemed to have an increasing awareness of the need for a “scientific level of understanding” and that they seemed to accept the dictum that “nothing is as practical as a good theory.” Yet the success of the National Training Laboratories, which he helped establish in 1946 and 1947, does seem to vindicate his optimism. First held at Bethel, Maine, the summer after Lewin’s death, these sessions have since expanded into a nationwide network serving the needs of professional men. They provide a link between these professional men and the resources of the behavioral sciences and the growing technology of re-education of attitudes, values, and behavior.

Persisting influence . Current research directly derived from Lewin’s work is being carried on by Cartwright and his colleagues, who are working on the development and use of mathematical concepts that are coordinated with life-space phenomena; at the Research Center for Group Dynamics at the University of Michigan (it was founded by Lewin at MIT and moved to Michigan after his death) and at university centers founded by some of his students, for example, by Festinger, Schachter, Deutsch, Thibaut, and Kelley; by Barker and his colleagues, working on psychological ecology; by French, Bavelas, Marrow, Cook, and others, who are coordinating organizational field experiments; and by Lippitt and his colleagues at the Center for Research on Utilization of Scientific Knowledge, the title of which is a key to its activities.

Ronald Lippitt

[See alsoField Theory. Other relevant material may be found inDevelopmental Psychology; Gestalt Theory; Groups; Systems Analysis, article onPsychological Systems; Thinking, article onCognitive Organization AND Processes.]

WORKS BY LEWIN

1917 Die psychische Tatigkeit bei der Hemmung von Willensvorgangen und das Grundgesetz der Assoziation. Zeitschrift fur Psychologic 77:212-247.

(1935-1946) 1948 Resolving Social Conflicts: Selected Papers on Group Dynamics. New York: Harper.

1936 Principles of Topological Psychology. New York: McGraw-Hill.

(1939-1947) 1963 Field Theory in Social Science: Selected Theoretical Papers. Edited by Dorwin Cart-wright. London: Tavistock.

1941 Barker, Roger; Dembo, Tamara; and Lewin, KurtFrustration and Regression: An Experiment With Young Children. University of Iowa Studies in Child Welfare, vol. 18, no. 1. Iowa City: Univ. of Iowa Press.

1943 Forces Behind Food Habits and Methods of Change. National Research Council,Bulletin 108:35-65.

(1945) 1948 Lewin, Kurt; and Grabbe, Paul Conduct, Knowledge, and Acceptance of New Values. Pages 56–68 in Kurt Lewin, Resolving Social Conflicts: Selected Papers on Group Dynamics. New York: Harper. → First published in Volume 1 of the Journal of Social Issues.

1953 Studies in Group Decision. Pages 287–301 in Dorwin Cartwright and Alvin Zander (editors), Group Dynamics: Research and Theory. Evanston, 111.: Row, Peterson. → Selections from writings first published between 1943 and 1947.

SUPPLEMENTARY BIBLIOGRAPHY

Ach, N. 1910 Über den Willensakt und das Temperament: Eine experimented Untersuchung. Leipzig: Quelle & Meyer.

Adler, D. L. 1939 Types of Similarity and the Substitute Value of Activities at Different Age Levels. Ph.D. dissertation, State Univ. of Iowa.

Barker, Roger G.; and Wright, Herbert F. 1954 Mid-west and Its Children. Evanston, 111.: Row, Peterson.

Cartwright, Dorwin 1942 The Effect of Interruption, Completion and Failure Upon the Attractiveness of Activities. Journal of Experimental Psychology 31: 1-16.

Cartwright, Dorwin 1959 Lewinian Theory as a Contemporary Systematic Framework. Volume 2, pages 7–91 in Sigmund Koch (editor), Psychology: The Study of a Science. New York: McGraw-Hill.

Coch, Lester; and French, John R. P. Jr. 1948 Overcoming Resistance to Change. Human Relations 1: 512-532.

Dembo, Tamara 1931 Der Ärger als dynamisches Problem. Untersuchungen zur Handlungs- und Affektpsychologie, 10. Psychologische Forschung 15:1-144.

Deutsch, Morton 1954 Field Theory in Social Psychology. Pages 181–222 in Gardner Lindzey (editor), Handbook of Social Psychology, Volume 1: Theory and Method. Cambridge, Mass.: Addison-Wesley.

Escalona, Sibylle 1954 The Influence of Topological and Vector Psychology Upon Current Research in Child Development: An Addendum. Pages 971–983 in Leonard Carmichael (editor), Manual of Child Psychology. 2d ed. New York: Wiley.

Ezriel, H. 1956 Experimentation Within the Psychoanalytic Session. British Journal for the Philosophy of Science 7:29-48.

Festinger, Leon; Schachter, Stanley; and Back, Kurt (1950) 1963 Social Pressures in Informal Groups: A Study of Human Factors in Housing. Stanford Univ. Press.

Frank, Jerome D. 1935 a Individual Differences in Certain Aspects of the Level of Aspiration.American Journal of Psychology 47:119-128.

Frank, Jerome D. 1935 b The Influence of the Level of Performance in One Task on the Level of Aspiration in Another. Journal of Experimental Psychology 18: 159-171.

Freund, Alex 1930 Psychische Sattigung im Menstruum und Intermenstruum. Untersuchungen zur Hand-lungs- und Affektpsychologie, 7. Psychologische Forschung 13:198-217.

Hoppe, Ferdinand 1931 Erfolg und Misserfolg. Untersuchungen zur Handlungs- und Affektpsychologie, 9. Psychologische Forschung 14:1-62.

Kalhorn, Joan 1944 Values and Sources of Authority Among Rural Children. Pages 99–152 in Kurt Lewin et. al., Authority and Frustration. University of Iowa Studies in Child Welfare, vol. 20. Iowa City: Univ. of Iowa Press.

Karsten, Anitra 1928 Psychische Sattigung. Untersuchungen zur Handlungs- und Affektpsychologie, 5. Psychologische Forschung 10:142-254.

Kelley, Harold H. 1950 The Warm–Cold Variable in First Impressions of Persons. Journal of Personality 18:431-439.

Kounin, Jacob S. 1941 Experimental Studies of Rigidity: 1-2. Character and Personality 9:251-282. → Part 1: The Measurement of Rigidity in Normal and Feeble-minded Persons. Part 2: The Explanatory Power of the Concept of Rigidity as Applied to Feeblemindedness.

Leeper, Robert W. 1943 Lewin’s Topological and Vector Psychology: A Digest and a Critique. Eugene: Univ. of Oregon.

Lissner, Kate 1933 Die Entspannung von Bediirfnissen durch Ersatzhandlungen. Untersuchungen zur Handlungs- und Affektpsychologie, 18. Psychologische Forschung 18:218-250.

Mahler, Wera 1933 Ersatzhandlungen verschiedenen Realitätsgrades. Untersuchungen zur Handlungs- und Affektpsychologie, 15. Psychologische Forschung 18: 27-89.

Ovsiankina, Maria VON 1928 Die Wiederaufnahme unterbrochener Handlungen. Untersuchungen zur Handlungs- und Affektpsychologie, 6. Psychologische Forschung 11:302-379.

Pepitone, Albert 1950 Motivational Effects in Social Perception. Human Relations 3:57-76.

Seashore, Harold C.; and Bavelas, Alex 1942 A Study of Frustration in Children. Pedagogical Seminary and Journal of Genetic Psychology 61:279-314.

Sliosberg, Sarah 1934 Zur Dynamik des Ersatzes in Spiel- und Ernstsituationen. Untersuchungen zur Handlungs- und Affektpsychologie, 19. Psychologische Forschung 19:122-181.

Thibaut, John W.; and Riecken, Henry W. 1955 Some Determinants and Consequences of the Perception of Social Causality. Journal of Personality 24:113-133.

White, Ralph K. 1951 Value-analysis: The Nature and Use of the Method. Glen Gardner, N.J.: Society for the Psychological Study of Social Issues.

Wright, M. Erik 1942 Constructiveness of Play as Affected by Group Organization and Frustration. Character and Personality 11:40-49.

Zeigarnik, Bluma 1927 Das Behalten erledigter und unerledigter Handlungen. Untersuchungen zur Hand-lungs- und Affektpsychologie, 3. Psychologische Forschung 9:1-85.

Lewin, Kurt 1890-1947

BIBLIOGRAPHY

Kurt Lewin was a psychologist with wide-ranging interests in psychological theory, child development, personality, social psychology, and social issues. He was born on September 9, 1890, to a Jewish family in Prussia. His family moved to Berlin in 1905 to provide access to better educational institutions for their children. Lewin entered the University of Berlin in 1910 and completed requirements for the PhD in 1914, under the direction of Carl Stumpf (1848–1936), director of the psychology laboratory since 1894. Lewin then enlisted in the kaiser’s army as a private, rose to the rank of lieutenant, was wounded in combat and awarded the Iron Cross. After discharge from the military, he returned to the university and began lecturing and conducting research, receiving an appointment as privatdozent in 1921. He was promoted to Aussenordenlicher Professor in 1927. In 1932 Lewin accepted an appointment as visiting professor at Stanford University. His sojourn allowed him to form friendships with a number of American psychologists who assisted him in immigrating to the United States after Adolf Hitler (1889–1945) and the Nazis took control of Germany in 1933. Lewin held a two-year appointment at Cornell University, moved to the University of Iowa from 1935 to 1944, and then to the Massachusetts Institute of Technology from 1944 until his death, from a heart attack, on February 12, 1947.

While in Berlin, Lewin began to study psychological issues considered too complex by the experimental psychologists of the time. He was interested in child development, human motivation and emotion, and personality. He considered the development of theories about these processes to be critical, and the use of experiments to test theory-based hypotheses as essential to progress in psychology. Lewin’s overarching theoretical approach was field theory, which asserted that human behavior was a function both of the person and the environmental forces acting on the person at the time, giving rise to his famous equation B (behavior) = f (function)[ P (person), E (environment)]. He and his students designed experiments in which theoretically defined variables were manipulated by complex changes in the social and physical environment. Theories focusing on complex intrapsychic processes and equally complex experimental manipulations were Lewin’s unique contributions to the psychology of his time, as well as his legacy in the psychology that would develop after his death. Two books, A Dynamic Theory of Personality (1935) and Principles of Topological Psychology (1936), provide systematic treatments of his approach. His many experimental reports display his innovations in research methods. Early criticisms of Lewin’s work focused on the difficulty and unfamiliarity of the concepts he employed, as well as the complexity of the experimental protocols he used. Over time, these criticisms faded as the psychological issues he explored became important research topics, while the details of his theoretical work received less and less attention. His style of experimentation was adopted by his students and colleagues, notably Leon Festinger (1919–1989), and became a robust tradition in social psychology.

Lewin had a lifelong dream of establishing a research institute that would conduct applied research focused on social issues such as prejudice, intergroup conflict, and social change. He succeeded in establishing the Research Center for Group Dynamics at MIT in 1944, and the Commission on Community Interrelations for the American Jewish Congress in 1945 in New York. An outgrowth of this work was the development of the National Training Laboratories, within which the T-group, or sensitivity training, was created.

Lewin is regarded by many social psychologists as the father of their discipline. He is certainly one of the field’s towering ancestral figures, for two reasons. His unique combination of theory with bold experimentation provided the conceptual and methodological tools to study complex human social interaction. And, from his days in Berlin until his death in Massachusetts, he attracted and inspired dozens of students who used those tools to develop many of the central theories and findings in social psychology, including group dynamics, level of aspiration, social comparison processes, and action research.

SEE ALSO Social Psychology

BIBLIOGRAPHY

Lewin, Kurt. 1935. A Dynamic Theory of Personality. Trans. Donald Adams and Karl Zener. New York: McGraw-Hill.

Lewin, Kurt. 1936. Principles of Topological Psychology. Trans. Fritz Heider and Grace M. Heider. New York: McGraw-Hill.

Marrow, Alfred J. 1969. The Practical Theorist: The Life and Work of Kurt Lewin. New York: Basic Books.

Darwyn E. Linder

Kurt Lewin

1890-1947
American social psychologist who carried out researches that are fundamental to the study of the dynamics and the manipulation of human behavior. He is the originator of field theory.

Kurt Lewin was born in Mogilno, Prussia, on September 9, 1899. He studied at the universities of Freiburg and Munich and completed his doctorate at the University of Berlin in 1914. He taught in Berlin from 1921 until the advent of Hitler to power in 1933, when he emigrated to the United States. He was visiting professor at Stanford and at Cornell before receiving an appointment as professor of child psychology in the Child Welfare Research Station of the State University of Iowa in 1935.

In 1945 he left Iowa to start the Research Center for Group Dynamics at the Massachusetts Institute of Technology. He also served as visiting professor at the University of California, Berkeley, and at Harvard.

At Iowa, Lewin and his associates conducted notable research on the effect of democratic, autocratic, and laissez-faire methods of leadership upon the other members of groups. Largely on the basis of controlled experiments with groups of children, Lewin maintained that contrary to popular belief the democratic leader has no less power than the autocratic leader and that the characters and personalities of those who are led are rapidly and profoundly affected by a change in social atmosphere. In effecting such changes on human behavior patterns, Lewin argued, the democratic group that has long-range planning surpasses both the autocratic and laissez-faire groups in creative initiative and sociality. As a general rule, he contended, the more democratic the procedures are, the less resistance there is to change.

The central factors to be considered if one wishes to transform a nondemocratic group into a democratic one are ideology, the character of its members, and the locus of coercive physical power within the group. Although coercive physical power is thus not the only factor to be considered, Lewin warns against the naive belief in the goodness of human nature, which overlooks the fact that ideology itself cannot be changed by teaching and moral suasion alone. It can be done only by a change in the distribution of coercive physical power. But he also warns that democratic behavior cannot be learned by autocratic methods. The members of the group must at least feel that the procedures are "democratic."

Lewin was a Gestalt psychologist, and that approach materially influenced him when he originated field theory. Strictly speaking, field theory is an approach to the study of human behavior, not a theory with content which can be used for explanatory, predictive, or control purposes. His work in this area has been judged as the single most influential element in modern social psychology , leading to large amounts of research and opening new fields of inquiry. According to Lewin, field theory (which is a complex concept) is best characterized as a method, a method of analyzing causal relations and building scientific constructs. It is an approach which maintains that to represent and interpret faithfully the complexity of concrete reality requires continual crossing of the traditional boundaries of the social sciences, rather than a progressive narrowing of attention to a limited number of variables. The theory, which requires an interdisciplinary approach to the understanding of concrete reality, has also been termed dynamic theory and topological psychology. It holds that events are determined by forces acting on them in an immediate field rather than by forces acting at

a distance. In the last analysis, it is a theory about theory building, or a metatheory.

Lewin believed that a social scientist has an obligation to use his resources to solve social problems. He helped found the Commission on Community Interrelations of the American Jewish Congress and the National Training Laboratories. Shortly after his death on February 12, 1947, the Research Center for Group Dynamics was moved to the University of Michigan, where it became one of two divisions of the Institute for Social Research and continued to exercise an important influence.

See also Gestalt psychology

Further Reading

Leeper, Robert W. Lewin's topological and vector psychology: a digest and a critique. 1943.

Marrow, Alfred Jay, The practical theorist: the life and work of Kurt Lewin, New York: Teachers College Press, 1977.