Marcus, Ruth Barcan (1921—)

American philosopher . Born Ruth Barcan in New York City, on August 2, 1921; daughter of Samuel Barcan and Rose (Post) Barcan; New York University, B.A., magna cum laude, 1941; Yale University, M.A., 1942, Ph.D., 1946; married Jules Marcus; children: James Spencer Marcus; Peter Webb Marcus; Katherine Hollister Marcus; Elizabeth Post Marcus.

Was research assistant at Institute for Human Relations (1945–46); was visiting professor at Northwestern University (1950–53, 1959); served as assistant and then associate professor, Roosevelt University, Chicago (1956–59, 1960–63); was professor of philosophy, University of Illinois, Chicago (1964–70); was head of the Department of Philosophy, University of Illinois, Chicago (1964–68); was professor of philosophy, Northwestern University (1970–73); was Reuben Post Halleck Professor of Philosophy, Yale University (1973—), living in New Haven, Connecticut.

Selected works:

"A Functional Calculus of First Order Based on Strict Implication" in Journal of Symbolic Logic (vol. 11, 1946); "The Deduction Theorem in a Functional Calculus of First Order Based On Strict Implication" in Journal of Symbolic Logic (vol. 12, 1947); "Elimination of Contextually Defined Predicates in a Modal System" in Journal of Symbolic Logic (vol. 15, 1950); "Strict Implication, Deductibility and the Deduction Theorem" in Journal of Symbolic Logic (vol. 18, 1953); "Modalities and Intensional Languages" in Syntheses (vol. 27, 1962); "Essentialism in Modal Logic" in Nous (vol. 1, 1967); (ed.) The Logical Enterprise (1975).

Ruth Barcan Marcus was born in New York City in 1921 and graduated magna cum laude from New York University in 1941. She earned her M.A. and Ph.D. at Yale University. Marcus was one of the few women who began to make forays into academic philosophy in the 20th century. Prior to this, women's opportunities for careers in that branch of academia had been limited, because they were largely restricted from even receiving an education within it. Marcus has had a very successful career as a professor at several prestigious American universities. She has published many articles in philosophy journals, particularly regarding symbolic logic in the subject of modal logic (systems that order the relationship between possibility and necessity) and how quantity can be accommodated in such systems, and also on the relationship between things being equal and their being identical.

Catherine Hundleby , M.A. Philosophy, University of Guelph, Guelph, Ontario, Canada