I. OVERVIEW

The magnitude and urgency of contemporary environmental problems—collectively known as the environmental crisis—form the mandate for environmental ethics: a reexamination of the human attitudes and values that influence individual behavior and government policy toward nature. The principal approaches to environmental ethics are "anthropocentrism," or the human-centered approach; "biocentrism," or the life-centered approach; and "ecocentrism," or the ecosystem-centered approach. Variously related to these main currents of environmental ethics are "ecofeminism" and "deep ecology." Moral "pluralism" in environmental ethics urges that we endorse all of these approaches and employ any one of them as circumstances necessitate.

Anthropocentrism

An anthropocentric environmental ethic grants moral standing exclusively to human beings and considers nonhuman natural entities and nature as a whole to be only a means for human ends. In one sense, any human outlook is necessarily anthropocentric, since we can apprehend the world only through our own senses and conceptual categories. Accordingly, some advocates of anthropocentric environmental ethics have tried to preempt further debate by arguing that a non-anthropocentric environmental ethic is therefore an oxymoron. But the question at issue is not, "Can we apprehend nature from a nonhuman point of view?" Of course we cannot. The question is, rather, "Should we extend moral consideration to nonhuman natural entities or nature as a whole?" And that question, of course, is entirely open.

In the mainstream of the Western cultural tradition, only human beings have been treated morally. Thus—at least for those working in that tradition—anthropocentrism is the most conservative approach to environmental ethics. Nevertheless, anthropocentric environmental ethicists have had to assume a more reactive than proactive posture and devote considerable effort to defending traditional Western moral philosophy against calls by bolder thinkers to widen the purview of ethics to encompass nonhuman natural entities and nature as a whole.

John Passmore and Kristin Shrader-Frechette were among the first to advocate a strictly anthropocentric approach to environmental ethics. Shrader-Frechette finds it "difficult to think of an action which would do irreparable harm to the environment or ecosystem, but which would not also threaten human well-being" (Shrader-Frechette, p.17). Since many of the anthropocentric ethics in the Western canon censure behavior that threatens human well-being (utilitarianism, most directly), she argues that there is therefore no need to develop a newfangled non-anthropocentric environmental ethic.

Some of the damage that people have done to the environment certainly does threaten human well-being. Global warming and the depletion of the ozone layer are notorious examples. But it is easy to think of other instances of environmental vandalism that do not materially threaten human well-being. David Ehrenfeld asks us to contemplate the probable demise of the endangered Houston toad, a victim of urban sprawl, that "has no demonstrated or conjectural resource value to man" (p. 650). But, as Ehrenfeld points out, the Houston toad is not unique in this respect. Thousands of other species in harm's way are nondescript "non-resources."

To morally censure the extinction of such species and other kinds of environmental destruction that do not materially threaten human well-being, must we abandon anthropocentrism? Amplifying the work of Mark Sagoff (1988) and Eugene C. Hargrove (1989), Bryan Norton (1987), the leading contemporary apologist for anthropocentric environmental ethics, argues that we should enlarge our conception of human well-being instead. In addition to goods (energy, foods, medicines, raw materials for manufacture) and services (crop pollination, oxygen replenishment, water purification), an undegraded natural environment contributes to human well-being in important psychological, spiritual, and scientific ways. Scenery unmarred by strip mines or clear cuts and undimmed by dirty air is important to human aesthetic satisfaction. Clean air and water, open spaces and green belts, complex and diverse landscapes, national parks and wilderness playgrounds are important human "amenities." Experiencing the solitude of wilderness and the otherness of wild things is an important aspect of human religious experience. Even if no one will be materially worse off after the extinction of "non-resource" species before science has a chance to discover and study them, important subject matter for pure, disinterested human knowledge will nevertheless have been irredeemably lost. Norton also suggests that contact with and care for the integrity of the natural environment can also be "transformative"; it can make better people of us.

Additionally, Norton argues that we should, as a matter of intergenerational justice, ensure that future human beings will be able to enjoy bountiful natural resources, a whole and functioning ecosystem, the full spectrum of environmental amenities, and the opportunity to partake of the psycho-spiritual experiences afforded by nature and to explore ecology and taxonomy intellectually. If we make our conception of human well-being both wide and long, he thinks that we may ground an adequate and effective environmental ethic without sailing off into the unfamiliar and treacherous waters of non-anthropocentrism.

The principal reason Norton offers for preferring an anthropocentic approach to environmental ethics is pragmatic. Anthropocentrism and non-anthropocentrism, he argues, support the same environmental policies. Norton (1991) calls this practical equivalence of anthropocentrism and non-anthropocentrism the "convergence hypothesis." Why then advocate non-anthropocentrism? Most people, including most environmentalists, he claims, accept the familiar and venerable idea that human beings are ends-in-themselves deserving moral standing. On the other hand, the suggestion that all living beings (and species and ecosystems) ought to be granted a similar status is unfamiliar and controversial. If we rest environmental ethics on as broad and firm a foundation as possible, we can best ensure its rapid implementation. Indeed, Norton suggests that the vigorous philosophical effort to develop non-anthropocentric approaches to environmental ethics has actually done the beleaguered environment a disservice. The environmental movement, as a result, has been divided over purely intellectual issues that have little if any practical import.

Norton's empirical claim that most people and even most environmentalists are anthropocentrists is supported only anecdotally. But opinion polls and the outcome of political contests suggest that most people probably have narrower allegiances—to self-interest, to institutional interests, to class interests, or to national interests—than to present and future collective or general human interests, very broadly construed. On the other hand, a growing minority of environmentalists seem to doubt the philosophical foundations of anthropocentrism. Are human beings really created in the image of God—the idea upon which anthropocentrism in Western religious ethics is founded? Are we uniquely self-conscious, rational, autonomous (some of the foundations of anthropocentrism in Western moral philosophy)? Must every being possess such characteristics to qualify for moral treatment? One may agree with the convergence hypothesis—that practical environmental goals are as well served by anthropocentric as by nonanthropocentric environmental ethics—but disagree that anthropocentrism is philosophically defensible. Hence, the question of the philosophical merits—the truth, as it were, of anthropocentrism—remains open.

Norton's convergence hypothesis, furthermore, over-looks an important difference between the way anthropocentric and non-anthropocentric environmental ethics support the same environmental policies. Suppose, as non-anthropocentrists variously argue, that the environment is "intrinsically" as well as "instrumentally" valuable—that is, that the environment is valuable for its own sake as well as for all the benefits, tangible and intangible, that it provides human beings. Warwick Fox decisively argues that such a supposition would shift the burden of proof from those who would disinterestedly preserve the environment to those who would destroy it for personal gain:

If the nonhuman world is only considered to be instrumentally valuable then people are permitted to use and otherwise interfere with it for whatever reasons they wish.… If anyone objects to such interference then, within this framework of reference, the onus is clearly on the person who objects to justify why it is more useful to humans to leave that aspect of the nonhuman world alone. If, however, the nonhuman world is considered intrinsically valuable then the onus shifts to the person who would want to interfere with it to justify why they should be allowed to do so; anyone who wants to interfere with any entity that is intrinsically valuable is morally obliged to be able to offer sufficient justification for their actions. (Fox, 1993, p. 101)

Norton, for example, might object to lumber companies cutting down redwood forests because the remaining redwood forests are of greater benefit to present and future human generations as amenities than as raw material for decks and hot tubs. But to preserve the remaining redwood forests, Norton would have to persuade a court to issue an injunction preventing lumber companies from harvesting redwoods, based on the assertion that the trees, while living, are more useful to human beings as psycho-spiritual and transformative resources than cut down and sawed up as consumptive resources. If, on the other hand, the trees were regarded as being intrinsically valuable, then a lumber company would have to make a case in court that the utility of redwood forests as raw material is so enormous as to justify their destruction. Thus, although Norton may be correct in claiming that a long and wide anthropocentric environmental ethic supports the same policies as nonanthropocentric environmental ethics—in the case at hand, the policy of preserving redwood forests—he cannot correctly claim that it would do so as forcefully.

Biocentrism

At first, theories of environmental ethics that morally enfranchise both individual living beings and natural wholes, such as species and ecosystems, were called "biocentric." Then, Paul W. Taylor (1986) commandeered the term to characterize his militantly individualistic theory of environmental ethics. Not only in deference to Taylor's influence and authority, but in deference to the literal sense of the term ("life-centered"), "biocentrism" in this discussion refers to theories of environmental ethics that morally enfranchise living beings only. Since species and ecosystems are not, per se, living beings, a biocentric theory would not accord them any moral standing.

Although animal welfare ethics and environmental ethics are by no means the same, biocentrism is launched from a platform provided by animal welfare ethics. Both attempt to extend our basic anthropocentric ethics—which, generally speaking, prohibit harming human "others" or violating their rights—to a more inclusive class of individuals: animal welfare ethics to various kinds of animals, biocentric environmental ethics to all living beings.

Peter Singer and Tom Regan, the principal architects of contemporary animal welfare ethics, exposed anthropocentric ethics to a dilemma. If the criterion for moral standing is pitched high enough to exclude all nonhuman beings, it will also exclude some human beings; but if it is pitched low enough to include all human beings, it will also include a large and diverse group of nonhuman animals.

An anthropocentrist may follow such philosophers as René Descartes and Immanuel Kant and proffer some highly esteemed and peculiarly human capacity—such as the capacity to reason, to speak, or to be a moral agent—as the qualification a being must possess to deserve ethical consideration. However, if practice is to be consistent with theory, anthropocentrism, so justified, should permit people who cannot reason or speak or who are not morally accountable for their behavior—human infants, the severely retarded, and the abjectly senile, for example—to be treated in the same ways that it permits animals to be treated: used as experimental subjects in painful biomedical research, hunted for sport, slaughtered and processed into dog food, and so on. To obviate these repugnant implications, Singer (1975) suggests that we follow Jeremy Bentham, the founder of utilitarian ethics, and settle upon sentience, the capacity to experience pleasure and pain, as a less hypocritical—and arguably a more relevant—qualification for moral consideration. That standard would secure the ethical standing of the so-called marginal cases, since irrational, unintelligent, or irresponsible people are all capable of experiencing pleasure and pain. But it would open membership in the moral community to all other sentient beings as well. If, as Bentham asserted, pleasure is good and pain is evil, and if, as Bentham also asserted, we should try to maximize the one and minimize the other irrespective of who experiences them, then animal pleasure and pain should count equally with human pleasure and pain in all our moral deliberations.

Singer vigorously advocates vegetarianism. Ironically, however, Singer's Benthamic animal welfare ethic is powerless to censure raising animals in comfort and slaughtering them painlessly to satisfy human dietary preferences. Indeed, one might even deduce from Singer's premises that people have a positive moral obligation to eat meat, provided that the animals bred for human consumption experience a greater balance of pleasure over pain during their short lives. For if everyone became a vegetarian, many fewer cows, pigs, chickens, and other domestic animals would be kept and thus many fewer animals would have the opportunity, for a brief time, to pursue happiness.

Recognizing these (and other) inadequacies of Singer's theory in relation to the moral problems of the treatment of animals, Tom Regan (1983) advocates a "rights approach." He argues that some individual animals have "inherent value" because they are, like ourselves, not only sentient but "subjects of a life"—beings that are self-conscious, experience desire and frustration, and that anticipate future states of consciousness—that from their point of view can be better or worse. Inherent value, in turn, may be the grounds for basic moral rights.

Neither Singer's nor Regan's prototype of animal welfare ethics will also serve as environmental ethics. For one thing, neither provides moral standing for plants and all the many animals that may be neither sentient nor, more restrictively still, subjects of a life—let alone for the atmosphere and oceans, species and ecosystems. Moreover, concern for animal welfare, on the one hand, and concern for the larger environment, on the other, often lead to contradictory indications in practice and policy. Examples follow: Advocates of animal liberation and rights frequently oppose the extermination of feral animals competing with native wildlife and degrading plant communities on the public ranges; they characteristically demand an end to hunting and trapping, whether environmentally benign or necessary; and they may prefer to let endangered plant species become extinct, rather than save them by killing sentient or subject-of-a-life animal pests.

On the other hand, animal welfare ethics and environmental ethics lead to convergent indications on other points of practice and policy. Both should resolutely oppose "factory farming": animal welfare ethics because of the enormous amount of animal suffering and killing involved; environmental ethics because of the enormous amount of water used and soil eroded in meat production. Both should staunchly support the preservation of wildlife habitat: animal welfare ethics because nature reserves provide habitat for sentient subjects; environmental ethics because many other forms of life, rare and endangered species, and the health and integrity of ecosystems are accommodated as well.

Despite the differences, animal welfare ethics may be regarded as "on the way to becoming" full-fledged environmental ethics, according to Regan (1983, p. 187). Animal welfare ethicists went the first leg of the philosophical journey by plausibly lowering the qualifying attribute for moral consideration. Albert Schweitzer (1989), Kenneth Goodpaster (1978), Robin Attfield (1983), and Paul Taylor (1986) variously suggest pitching it lower still—from being sentient to being alive.

Schweitzer, writing long before the efflorescence of contemporary animal welfare and environmental ethics literature, appears to ground his "reverence for life" ethic in the voluntarism of Arthur Schopenhauer:

Just as in my own will-to-live there is a yearning for more life … so the same obtains in all the will-to-live around me, equally whether it can express itself to my comprehension or whether it remains unvoiced.

Ethics consists in this, that I experience the necessity of practising the same reverence for life toward all will-to-live, as toward my own. (Schweitzer, 1989, pp. 32–33)

Contemporary biocentrism appears to have been inspired by Joel Feinberg's observations about the moral importance of interests and the range of entities to which interests may be attributed. The foundational role of the concept of "conation" (an often unconscious striving, reified by Schopenhauer as the "will-to-live") in Feinberg's characterization of interests unifies contemporary Anglo-American biocentric environmental ethics with Schweitzer's version. According to Feinberg:

A mere thing, however valuable to others, has no good of its own … [because] mere things have no conative life: no conscious wishes, desires, and hopes; or urges or impulses; or unconscious drives, aims, and goals; or latent tendencies, directions of growth, and natural fulfillments. Interests must be compounded somehow out of conations; hence mere things have no interests, A fortiori, they have no interests to be protected by legal or moral rules. Without interests a creature can have no "good" of its own the achievement of which can be its due. Mere things are not loci of value in their own right, but rather their value consists entirely in their being objects of other beings' interests. (Feinberg, pp. 49–50)

The clear implication of this passage is that the "insuperable line," as Bentham called the boundary separating beings who qualify for moral consideration from those who do not, falls between living beings and nonliving things, not between sentient animals and insentient animals and plants. Why? Because even plants have "unconscious drives, aims, and goals; or latent tendencies, directions of growth, and natural fulfillments." Feinberg, nevertheless, goes on to deny that plants have interests of their own. His reasons for doing so, however, appear to be less clear and decisive than his derivation of interests from conations and his argument that beings who have interests deserve moral consideration.

Kenneth Goodpaster (1978) argues that all living beings, plants as well as animals, have interests. And he argues, appealing to Feinberg as an authority, that beings who have interests deserve "moral considerability"—a term that Goodpaster uses to indicate precisely the ethical status of moral patients (those on the receiving end of an action), as distinct from moral agents (those who commit an act). Goodpaster agrees with Singer that their sentience is a sufficient condition for extending moral considerability to animals, but he disagrees that it is a necessary one, because sentience evolved to serve something more fundamental—life: "Biologically, it appears that sentience is an adaptive characteristic of living organisms that provides them with a better capacity to anticipate, and so avoid, threats to life.…[T]he capacities to suffer and enjoy are ancillary to something more important, rather than tickets to considerability in their own right" (p. 316).

Goodpaster's life-principle ethic is modest. All living beings are morally considerable, but all may not be of equal moral "significance." He leaves open the question of how much weight we should give to a plant's interests when they conflict with a sentient creature's or with our own. Paul Taylor (1986) has struck a much stronger and bolder stance and argued that all living beings are of equal "inherent worth."

Taylor bases a living being's inherent worth on the fact that it has a good of its own, quite independent of our anthropocentric instrumental valuation of it and quite independent of whether the organism is sentient or cares. Light, warmth, water, and rich soil are good for a sprig of poison ivy, though poison ivy may not be good for us. Unlike machines and other purposeful artifacts that we design to serve our own ends, organisms are ends-in-themselves. Most generally, they strive to reach a state of maturity and to reproduce. Therefore, just as we insist that others not interfere with our own striving and thriving, so, Taylor urges, expressly patterning his reasoning on Kant's, we should respect the striving and thriving of all other "teleological centers of life." Kant argued that we should respect, as individuals-in-themselves, all rational, autonomous beings equally. And Taylor argues that we should respect equally all living beings because they too are ends-in-themselves.

Because biocentrism is concerned exclusively with biological individuals, not biological wholes, it is an approach to environmental ethics that seems at once so restrictive that it would be impossible to practice, and an approach that has scant relevance to the set of problems constituting the environmental crisis. How can we do anything at all, if, before we act, we are obliged to consider the interests of each and every living being that we might affect? Why should we feel compelled to do so for the sake of the environment? Environmental concern focuses primarily on the spasm of abrupt massive species extinction and the loss of biodiversity generally, on rapid global warming and the erosion of stratospheric ozone, on soil erosion, water pollution, and the like; not on the welfare of individual grubs, bugs, and shrubs.

Schweitzer and Goodpaster frankly acknowledge the difficulty in practicing biocentrism. Schweitzer writes, "It remains a painful enigma how I am to live by the rule of reverence for life in a world ruled by creative will which is at the same time destructive will" (1989, p. 35). And Goodpaster writes:

The clearest and most decisive refutation of the principle of respect for life is that one cannot live according to it, nor is there any indication in nature that we were intended to. We must eat, experiment to gain knowledge, protect ourselves from predation.… To take seriously the criterion being defended, all these things must be seen as somehow morally wrong. (p. 310)

Both reasonably suggest that we can at least respect the interests of other living beings when they do not conflict with our own. According to Goodpaster, biocentrism is not suicidal. It requires only that we use living beings considerately and sensitively. Schweitzer thinks that biocentrism permits us to injure or destroy other forms of life, but only when doing so is necessary and unavoidable.

Taylor's egalitarianism renders the practicability problem of biocentrism virtually insurmountable (Wenz). Starting with any individual's right to self-defense, he rationalizes our annihilating disease organisms with medicines and goes on from there to defend our killing and eating other living beings to feed ourselves. But the satisfaction of any "nonbasic" human interest, according to Taylor, must be forgone if it violates the basic interests of another teleological center of life. So it would seem that strict adherence to biocentric egalitarianism would require one to live a life of sacrifice that would make a monk's life appear opulent.

Writing before the advent of the environmental crisis, Schweitzer was not intending to address its problems. He seems genuinely concerned, rather, with the welfare of individual living beings. Thus, it would be unfair and anachronistic to criticize his reverence-for-life ethic for being largely irrelevant to the set of problems constituting the environmental crisis. Taylor, on the other hand, represents his biocentric ethic as an environmental ethic. And he is clearly aware that contemporary environmental concerns focus on such things as species loss and ecosystem deterioration. But he remains antagonistic to the holistic environmental ethics crafted in response to such concerns. He prefers to think of the extinction of species and destruction of ecosystems in anthropocentric, rather than in biocentric or ecocentric terms. Goodpaster, on the other hand, invokes "concern felt by most person about 'the environment'" as a reason for trying to extend moral considerability to all living beings (p. 309). He seems, moreover, to be aware that to actually reach the concern felt by most persons about the environment, biocentrism would have to "admit of application to … systems of entities heretofore unimagined as claimants on our moral attention (such as the biosystem itself)" (p. 310). Having once mentioned systems of entities, however, Goodpaster lavishes all his attention on individual living beings and has nothing at all to say about how biocentrism might actually admit of application to species, ecosystems, and the biosphere as a whole.

Biocentrism may be not only irrelevant to actual environmental concerns, it could aggravate them. Biocentrism can lead its proponents to a revulsion toward nature—giving an ironic twist to Taylor's title, Respect for Nature—because nature seems as indifferent to the welfare of individual living beings as it is fecund. Schweitzer, for example, comments that

the great struggle for survival by which nature is maintained is a strange contradiction within itself. Creatures live at the expense of other creatures. Nature permits the most horrible cruelties.… Nature looks beautiful and marvelous when you view it from the outside. But when you read its pages like a book, it is horrible. (1969, p. 120)

Ecocentrism

Though the term "ecocentrism" is a contradiction of the phrase "ecosystem-centered," ecocentrism would provide moral considerability for a spectrum of nonindividual environmental entities, including the biosphere as a totality, species, land, water, and air, as well as ecosystems. The various ecologically informed holistic environmental ethics that may appropriately be called ecocentric are less closely related, theoretically, than either the anthropocentric or biocentric families of environmental ethics.

Lawrence E. Johnson has attempted to generate an environmental ethic that reaches species and ecosystems by a further extension of the biocentric approach. He does this not by making the criterion for moral considerability more inclusive but by attributing interests to species and ecosystems. Extensively developing the line of thought that Feinberg (1974) tentatively and ambiguously initiated, Johnson concludes that we should "give due respect to all the interests of all beings that have interests, in proportion to their interests"(p. 118). As this, his summary moral principle, suggests, Johnson follows Goodpaster in allowing that all interests are not equal and thus that all interested beings, though morally considerable, are not of equal moral significance. Johnson, however, provides no principle or method for hierarchically ordering interests and the beings who possess them; nor does he provide an ethical procedure for adjudicating conflicts of interest between people, animals, and plants, and, more difficult still, between all such individuals and environmental wholes.

In arguing that species have interests, Johnson exploits the fact that some biologists and philosophers of biology regard species not as classes of organisms but as spatially and temporally protracted individuals. To plausibly assign them interests, in other words, Johnson assimilates species to individual organisms. During the first quarter of the twentieth century, ecosystems (though then they were not so denominated) were represented in ecology as supraorganisms. Johnson adopts this characterization of ecosystems, as doing so allows him to attribute interests to ecosystems by assimilating them to individual organisms, just as in the case of species. Finally, Johnson points out that James Lovelock (1979) has suggested that the Earth as a whole is an integrated living being (named Gaia); if so, it (she) too may have interests and thus may be morally considerable. Adopting nonstandard, obsolete, or highly controversial scientific models of species, ecosystems, and the biosphere is the price Johnson pays to purchase moral considerability for these natural wholes. His attempt to add an ecocentric dimension to his essentially biocentric approach to environmental ethics is thus seriously compromised.

Holmes Rolston's ecocentric environmental ethic, like Johnson's, is launched from a biocentric platform. Rolston (1988) endorses the central tenet of biocentrism that each living being has a good of its own and that having a good of its own is the ground of a being's intrinsic value. And upon the existence of intrinsic value in nature he founds our duties to the natural world in all its aspects.

Rolston's biocentrism, in sharp contrast to Taylor's, is inegalitarian. Rolston finds more intrinsic value in beings that sense their own good, that feel hurt when harmed, than in those that lack consciousness. And Rolston finds the most intrinsic value of all in normal adult human beings because we are rational and fully self-conscious as well as conative and sentient.

Rolston avoids the scientifically suspect route that Johnson takes to enfranchise ethically such environmental wholes as species and ecosystems. Rolston argues instead that since the most basic telos of a teleological center of life is to be "good of its kind" and to reproduce its species, then its kind or species is its primary good. Species per se do not have a good of their own, but as the most basic good of beings that do have a good of their own, they too can be said to possess intrinsic value. The myriad natural kinds or species, however, evolved not in isolation but in a complex matrix of relationships—that is, in ecosystems. Thus, though not themselves teleological centers of life, either, some intrinsic value rubs off on ecosystems in Rolston's theory of environmental ethics. Rolston coins a special term, "systemic value," to characterize the value of ecosystems.

Systemic value does not seem to be entirely parallel, logically or conceptually speaking, to intrinsic value in Rolston's theory of environmental ethics. Rather, it seems that a necessary condition for the existence of the things that he believes do have intrinsic value—beings with a good of their own and the goods (their kinds or species) that such beings strive to actualize and perpetuate—is the existence of their natural contexts or matrices. Like the moon that shines by a borrowed light, systemic value seems to be a kind of reflected intrinsic value. Rolston finds a similar sort of derivative intrinsic value, "projective value," in elemental and organic evolutionary processes going all the way back to the Big Bang, since such processes eventually produced (or "projected") living beings with goods of their own.

Rolston's theory of environmental ethics hierarchically orders intrinsically valuable individuals in a familiar and conventional way. Human beings are at the pinnacle of the value hierarchy, followed by the higher animals, and so on, pretty much as in the Great Chain of Being envisioned by many Western philosophers of yore. Rolston is prepared to invoke his hierarchical arrangement of intrinsically valuable kinds of beings to resolve biocentric moral conundrums. For example, he expressly argues that it is morally permissible for people to kill and eat animals and for animals to kill and eat plants. Though such a hierarchical ordering of intrinsically valuable beings jibes with tradition and uncultivated common sense, it may not always jibe with, and hence may not adequately justify, our considered environmental priorities. Most environmentalists, faced with the hard choice of saving a sensitive, subjective dog or an unconscious, merely conative thousand-year-old redwood tree, would probably opt for the tree—and not only because redwoods are becoming rare. Pressed for good reasons for making this choice, Rolston might answer that an environmentally ethical agent is perfectly free, in reaching a decision to give priority to the redwood over the dog, to add to their intrinsic value the way standing redwoods are valued anthropocentrically and the way they serve the systemic value of ecosystems. The ethical agent can legitimately add the redwood's economic value to its systematic value, intrinsic value, aesthetic value, or religious value. How the intrinsic value of species and the systemic value of ecosystems fits into Rolston's value hierarchy is not entirely clear. Is a plant species more or less intrinsically valuable than a specimen of Homo sapiens, or than a specimen of Ovis aries (domestic sheep)?

According to Regan (1981) the very possibility of an environmental ethic turns on constructing a plausible theory of intrinsic (or "inherent") value in nature. He argues that anthropocentric environmental ethics are "management ethics," ethics for the "use" of the environment, not environmental ethics proper. Regan sets clear and stringent conditions for such value: first, it must be strictly objective, independent of any valuing consciousness; second, it must attend some property or set of properties that natural entities possess; and third, it must be normative, it must command ethical respect or moral considerability.

Rolston's basing a being's intrinsic value on its having a good of its own seems to meet the first two of these conditions, but possibly not the third. Before consciousness evolved, living beings had goods of their own; they could be harmed if not hurt; they had interests, whether they cared or not. The move, however, from the hardly disputable fact that living beings objectively possess goods of their own to the assertion that they have objective intrinsic value may turn on an ambiguity in the meaning of "good."

The word "good" has a teleological as well as a normative sense. All living beings have goods of their own in the teleological sense. They have, in other words, ends that were not imposed upon them—as the goods or ends of machines and other artifacts are—by beings other than themselves. But it is still possible to ask if such teleological goods generate normative goods. At this point in the argument, the smallpox and AIDS viruses are usually invoked as examples of organisms that have goods of their own in the teleological sense of the term, but organisms that one would be loath to say are good in the normative sense of the term.

However this particular conceptual issue may be resolved, another, moral general one casts a very large and dark shadow on Rolston's claim of finding objective intrinsic value in nature. While Rolston is very careful not to buck prevailing scientific opinion on the sort of reality possessed by species, ecosystems, and evolutionary processes, his argument that intrinsic value exists objectively in nature does buck more general assumption of modern science. From the modern scientific point of view, nature is value-free. Goodness and badness, like beauty and ugliness, are in the eye of the beholder. According to this entrenched dogma of modern science, there can be no valuees without valuers. Nothing under the sun—no rational self-conscious person, no sentient animal, no vegetable, no mineral—has value of any kind, either as a means or an end, unless it is valued by some valuing subject.

The crisp objective/subjective distinction in modern science, however, has been undermined by the Heisenberg Uncertainty Principle in quantum physics, as the observation of subatomic entities unavoidably affects their state of being. Therefore, the modern scientific worldview has become problematic. Seizing upon this circumstance, J. Baird Callicott (1989), among others, has broached a value theory for environmental ethics that is neither subjective nor objective. Just as experimental physicists actualize the potential of an electron to be at a particular place by observing it, so, Callicott suggests, the potential value of an entity, both instrumental and intrinsic, is actualized by a valuer appreciating it.

Although it may eventually give way to a postmodern scientific worldview, the modern scientific worldview continues to reign supreme. The "land ethic" sketched by Aldo Leopold (1949) has been the moral inspiration of the nonanthropocentric wing of the contemporary popular environmental movement, in part because Leopold respects the subjectivity of value required by the modern scientific world view without at the same time reducing nature to natural resources.

Callicott (1987) claims that Leopold's ecocentric environmental ethic may be traced to the eighteenth-century moral philosophy of David Hume and Adam Smith, who think that feelings lie at the foundations of value judgments. While feelings fall on the subjective side of the great subject/object divide, Hume and Smith also point out that our feelings may be altruistic or other-oriented as well as selfish. Hence we may value others for their own sakes, as ends-in-themselves. Further, Hume and Smith note that in addition to sympathy for others, respectively, we also experience a "public affection" and, accordingly, value the "interests of society even on their own account."

In The Descent of Man, Charles Darwin (1874) adopted the moral psychology of Hume and Smith and argued that the "moral sentiments" evolved among human beings in conjunction with the evolution of society, growing in compass and refinement along with the growth and refinement of human communities. He also developed the incipient holism of Hume and Smith, flatly stating that primeval ethical affections centered on the tribe not its individual members.

Leopold, building directly on Darwin's theory of the origin and evolution of ethics, points out that ecology represents human beings to be members not only of multiple human communities but also of the "biotic community." Hence, "the land ethic simply enlarges the boundaries of the community to include soils, waters, plants, and animals, or collectively: the land.… It implies respect for … fellow members and also respect for the community as such" (Leopold, p. 204).

Animal welfare ethicists and biocentrists claim that Leopold's ecocentrism is tantamount to "environmental fascism." Leopold wrote—and his exponents affirm—that "a thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community [and] wrong when it tends otherwise" (pp. 224–225). If this is true, then not only would it be right deliberately to kill deer and burn bushes for the good of the biotic community, it would also be right to undertake draconian measures to reduce human overpopulation—the underlying cause, according to conventional environmental wisdom, of all environmental ills.

Providing for the possibility of moral consideration of wholes, however, does not necessarily disenfranchise individuals. The land ethic is holistic as well as (not instead of) individualistic, although in the case of the biotic community and its nonhuman members holistic concerns may eclipse individualistic ones. Nor does the land ethic replace or cancel previous socially generated human-oriented duties—to family and family members, to neighbors and neighborhood, to all human beings and humanity. Human social evolution consists of a series of additions rather than replacements. The moral sphere, growing in circumference with each stage of social development, does not expand like a balloon—leaving no trace of its previous boundaries. It adds, rather, new rings, new "accretions," as Leopold called each emergent social-ethical community. The discovery of the biotic community simply adds several new outer orbits of membership and attendant obligation. Our more intimate social bonds and their attendant obligations remain intact. Thus we may weigh and balance our more recently discovered duties to the biotic community and its members with our more venerable and insistent social obligations in ways that are entirely familiar, reasonable, and humane.

Ecofeminism

The term "ecofeminism" is a contraction of the phrase "ecological feminism," which may be understood as an analysis of environmental issues and concerns from a feminist point of view and, vice versa, as an enrichment and complication of feminism with insights drawn from ecology. Ecofeminism is both an approach to environmental ethics and an alternative feminism.

An axiom of ecofeminism is that, both historically and globally, men have dominated women and "man" has dominated nature. Further, many male-centered, culture-defining texts, such as the epics of Homer and Hesiod, the works of the ancient philosophers, and so forth, have associated women with nature and personified the Earth and nature generally as female (Griffin). The domination of women and nature appears to stem from a single source: patriarchy (literally, father-rule). Criticize and overcome patriarchy, the principal ideological force responsible for the domination of women, and one will at the same time have criticized and overcome the principal ideological force responsible for the degradation and destruction of nature. According to Marti Kheel, "for deep ecologists, it is the anthropocentric worldview that is foremost to blame.… Ecofeminists, on the other hand, argue that it is the androcentric worldview that deserves the primary blame" for the environmental crisis (p. 129).

Some environmentalists suspect such an analysis to be a thinly disguised ploy to divert the energies of the environmental movement into the feminist movement. Deep ecologist Warwick Fox (1989), for example, argues that a feminist environmental ethic focused on abolishing patriarchy is too self-serving, simplistic, and facile to be taken seriously as a panacea for environmental ills. Other movements, he points out, can make, and have made, the same implausible claim: If we only abolish the ideology of racism, capitalism, imperialism, and so on, then we will usher in the millennium and all will be right with the world, natural as well as social.

Karen J. Warren (1990) does not follow Kheel and blame the domination and subordination of nature by "man" on the domination and subordination of women by men. Rather, she argues, both forms of "oppression" are "twin" expressions of hierarchically ordered "value dualisms" reinforced with a "logic of domination." Critiques of anthropocentrism and androcentrism are mutually illuminating and complementary. A person opposed to the one ought to be opposed to the other—because subordination, domination, and oppression are wrong, whether of women by men or of nature by "man." Environmentalists should also be feminists and feminists, environmentalists. Ecofeminism is the union of the two.

An ecofeminist approach seeks to correct an alleged "male bias" in environmental ethical theory—a selection of concepts and methodology that ignores, discounts, or denigrates women's issues, concerns, and experience. Alison M. Jagger has suggested that modern Western ethics, "Enlightenment moral theory," is thoroughly male-biased since it portrays moral agents as being "disembodied, asocial, autonomous, unified, rational, and essentially similar to all other" agents (p. 367). In short, it abstracts, generalizes, universalizes. Intimately associated with this "Cartesian" moral psychology are such commonplaces of modern Western ethics as universal application of abstract principles and rules, impartiality, objectivity, rights, and the victory of synoptic and dispassionate reason over myopic and prejudicial feelings. Warren argues, accordingly, that "ecofeminism … involves a shift from a conception of ethics as primarily a matter of rights, rules, or principles predetermined and applied in specific cases to entities viewed as competitors in the contest of moral standing, to a conception of ethics as growing out of … defining relationships … and community" (pp. 141–142). She notes further that "ecofeminism makes a central place for [the more feminine, less male] values of care, friendship, trust, and appropriate reciprocity—values that presuppose that our relationships to others are central to our understanding of who we are" (p. 143).

It is surprising that ecofeminists have not warmly endorsed the Aldo Leopold land ethic, which grounds morality in such sentiments as love, sympathy, and fellow-feeling. The locus classicus for an environmental ethic growing out of "defining relationships" and "community" is found in Leopold's A Sand County Almanac (1949). Marti Kheel, however, castigates Leopold's land ethic, arguing that it epitomizes male bias. Leopold endorses hunting, historically a predominantly male activity, as a means not only of ecological management but also of experiencing our defining relationships with nature and cultivating a "love and respect" for "things natural, wild, and free."

Deep Ecology

Just as there are Democrats (with a capital "D," members of one of the two major political parties in the United States) and democrats (with a lower-case "d," persons, irrespective of party affiliation, who agree with Winston Churchill that democracy is the worst form of government except for all the others), so there are Deep Ecologists (with a capital "D" and "E") and deep ecologists (with a lower-case "d" and "e"). The latter, such as Aldo Leopold, think that ecology has profound philosophical implications that it transforms our understanding of the world in which we live and what it means to be a human being. Deep Ecologists, on the other hand, endorse the eight-point "platform" of Deep Ecology that Arne Naess co-authored with George Sessions (Devall and Sessions). Moreover, they downplay the importance of environmental ethics, and advocate "Self-[with a capital 'S'] realization," instead. In short, deep ecology is a philosophical orientation; Deep Ecology is an ideology.

Ethics per se, Deep Ecologists allege, assumes "social atomism," a conception of each individual self as externally related to all other selves and to unselfconscious nature (Fox, 1990). Therefore, Deep Ecologists suppose that an ethical act on the part of an atomic moral agent involves grudgingly considering the interests of other morally considerable beings equally and impartially with his or her own. But for people actually and consistently to behave ethically—as thus characterized—is as rare as it is noble. Therefore, even if environmental ethics could be broadly infused, environmental destruction and degradation would be little abated.

However, the metaphysical implications of ecology undermine the social atomism upon which ethics is supposedly premised. We human beings are internally, not externally, related to one another and to non-human natural entities and nature as a whole. "Others" cannot be cleanly and neatly distinguished from ourselves. Our relationships, natural as well as social, with "them" are mutually defining. We are embedded in communities, biotic as well as human. If we could only realize that the environing world is ultimately indistinguishable from ourselves, then we could enlist the powerful and reliable motive of self-interest in the effort to reverse environmental degradation and destruction (Naess).

The process of Deep Ecological Self-realization is experiential as well as intellectual. Through practice as well as study, we should cultivate a palpable sense of identification with the world. Nature-protecting behavior will flow from experiential identification with nature. Warwick Fox (1990) has suggested that Deep Ecology should actually be renamed "transpersonal ecology," since, as in transpersonal psychology, the goal of Self-(with a capital "S") realization involves self-(with a lower-case "s") transcendence.

Deep Ecology's suspicions about the efficacy of environmental ethics seems to be based upon a narrow characterization of ethics that excludes sentiment-based communitarian ethics like the Leopold land ethic and its ecofeminist correspondents. Ecofeminists have also sharply criticized Deep Ecology because it seems to "totalize" and "colonize" the "other" (Cheney; Plumwood). With the important exception of Naess, Deep Ecologists either explicitly or implicitly claim that the integrated, systemic ecological world view is true and regard other ways of constructing nature and the relationship of people to nature to be false. A cornerstone of feminism is openness to the experience of women, experience that is quite varied. The experience of all or even of most women may not jibe well with Deep Ecological Self-realization. Hence the Deep Ecologists' often doctrinaire assertions about how the world is really and truly organized and how we ought to experience it are anathema to most ecofeminists.

Pluralism

The term "pluralism" in ethics characterizes two things equally well.

What we might call "social pluralism" is the view that diverse and often mutually inconsistent ethical outlooks should be respected and that there may not be any single moral principle or set of principles, however basic, that all moral agents must acknowledge. Human rights, for example, may be widely acknowledged in the West, but not in other parts of the world; hence, from a social pluralist's point of view, for Western governments to try to impose standards of human rights upon non-Western societies is inappropriate.

Personal pluralism, on the other hand, is the view that a single moral agent may endorse a variety of different moral principles, some of which may be mutually inconsistent, and employ one or another in different morally charged situations. For example, in resolving ethical questions about diet, a personal pluralist might apply Singer's principle that one should not cause sentient beings unnecessary suffering and therefore decide not to eat factory-farmed meat. In resolving ethical questions about abortion, he or she might apply Schweitzer's reverence-for-life principle and vote for an anti-abortion candidate for public office. And, in resolving ethical questions about species conservation, the same person might embrace Leopold's principle that one should preserve the integrity, stability, and beauty of the biotic community and help save an endemic plant species by shooting the feral goats or pigs threatening it.

Social pluralism appears attractive because it seems to imply inclusiveness and tolerance. In extremis, however, social pluralism is vulnerable to the same sort of criticism that ethical relativism, in extremis, has attracted. A social pluralist recognizes no universal ethical values or principles, he or she has no means of ethically challenging any one else's sincerely held moral beliefs. Further, if there are no universal ethical values or principles upon which to base agreement, then radical and intractable differences of moral outlook are irreconcilable. How then can they be resolved except by coercion?

Personal pluralism arose in environmental ethics because finding a single moral principle that could guide our actions in respect to other people, animals, plants, species, ecosystems, the atmosphere, the oceans, and the biosphere proved difficult (Stone). Moreover, our inherently rich and complicated moral lives may be distorted if reduced to a single master principle of action and we are frequently misled if we try rigorously to follow one (Brennan). According to Mary Midgley (1992), we may read the history of Western ethical theory, from Plato and Aristotle to Singer and Leopold, not as a series of formulations of and justifications for competing master principles of action, but as a series of illuminating insights into human ethical experience that can deepen our moral reflection and help us to make wise practical choices.

Proponents and critics alike of personal pluralism have noted some obvious problems. An agent who has a variety of principles and their theoretical justifications at the ready, with no faithful commitment to any of them required, may be tempted to choose the most convenient or self-serving. But all ethics, whether pluralistic or unitary, assume good will on the part of moral agents. A more difficult problem is how to select which principle to apply when more than one is relevant at some moment of decision, and when those that are relevant indicate different and incompatible courses of action. But to demand an algorithmic solution to this problem is to beg the question against personal pluralism.

Moral principles, however, do not exist in an intellectual vacuum (Callicott, 1990). They are often derived from and are always associated with a complex of supporting ideas—usually an ethical theory, which is in turn supported by a moral philosophy. In choosing to act upon a moral principle, a personal moral pluralist thus also endorses—whether consciously or not—the ethical theory and ultimately the moral philosophy supporting it. But the ethical theories and moral philosophies supporting such popular principles as the Christian golden rule, the Aristotelian golden mean, the Kantian categorical imperative, the utilitarian greatest-happiness principle, and so on, offer radically different visions of nature and human nature. Are we morally autonomous rational ends-in-ourselves for whom nature exists only as means, as Kant argues; or are we vessels of pleasure and pain, equal in this morally relevant respect to all other sentient animals, as Singer holds? How can we be both at once?

Communitarianism

A communitarian moral philosophy might provide a coherent sense of self and world without compromising the richness and complexity of our moral lives or attempting to derive all ethical actions from a single principle. Suppose that ethics, as Darwin argued, is correlative to society; that at this stage of human social evolution, we are simultaneously members of many communities or societies, including families, neighborhoods, towns or cities, nation-states, the global human community, the mixed human-domestic animal community, and the biotic community; and that a spectrum of different and not always compatible duties and obligations grow out of our various social relationships—for example, to provide our children with affection, to watch our neighbors' houses when they are away on vacation, to donate old clothes to the Salvation Army, to pay our taxes, to relieve world hunger, to boycott factory-farmed meat, and to help preserve biodiversity.

Right and wrong behavior in respect to family and family members, humanity and human beings, the biotic community and wild animals and plants, grows out of the very different kinds of communal relationships that we bear in these very different cases. Hence what is right in the context of one kind of community (feeding domestic animals, who are members of the "mixed community," for example) may be wrong in another (feeding wild animals, who are members of the biotic community). A multiplicity of community-generated principles guides our actions, but this multiplicity is united and coordinated by a single general understanding of how our various duties arise and to whom they apply. A coherent moral outlook like this certainly does not automatically determine the best course of action when one's multiple duties conflict. But one can at least hope rationally to decide, in circumstances of hard choice, which of several relevant but conflicting duties is the most pressing because they can all be expressed in comparable and commensurable terms.

j. baird callicott (1995)

bibliography revised

SEE ALSO: Animal Welfare and Rights; Environmental Health; Environmental Policy and Law;Population Ethics; and other Environmental Ethics subentries

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