I. ETHICAL PERSPECTIVES ON THE TREATMENT AND STATUS OF ANIMALS

Normative ethical theory may be conceived as the systematic inquiry into the moral limits on human freedom. Philosophers and theologians throughout history and across cultures have offered different, often contradictory, answers to the central question of ethics thus conceived. Some have argued, for example, that the only justified limits on human freedom are those grounded in the rational self-interest of the agent, while others have maintained that the foundations of morality, and thus the basis of morally justified limitations on human freedom, are logically distinct from self-interest, though not from the dictates of reason. Still others have alleged that the foundations of morality have nothing to do with either reason or self-interest.

In view of the variety and conflicting nature of answers to the central question of normative ethics, it is hardly surprising that ethical theories sometimes offer strikingly different accounts of the moral status of those nonhuman animals we humans raise or hunt for food and clothing, use as beasts of burden, train to entertain us, and utilize as models for purposes of biomedical research. No philosopher or theologian has gone so far as to say that, from the moral point of view, there are no justified limits on what we may do to these animals. Even René Descartes, much celebrated for his theory that nonhuman animals are automata and thus incapable of feeling either pain or pleasure (Descartes, "Animals Are Machines," in Regan and Singer, 1976; 1989), is said to have treated his dog humanely. At a certain minimal level, then, all normative ethical theories speak with one voice. But at other levels, the differences are both real and deep.

Direct and Indirect Duties

These differences emerge clearly when we consider how competing theories answer two distinct but related questions. The first asks, What are the grounds for morally limiting human freedom when it comes to human interactions with nonhuman animals? The second asks, How extensive are these moral limits on human freedom? The former inquires as to why human freedom should be limited at all when our actions affect other animals; the latter challenges us to investigate how much our freedom should be limited. Of the two questions, the first is the more basic, for the reasons given in support of views about how much our freedom should be limited ultimately are based on views about why our freedom should be limited in the first place.

Two opposed possibilities present themselves as answers to the first, more basic question. One possibility holds that it is because of how animals themselves are affected or treated by human agents that we should limit our freedom. Viewed from this perspective, nonhuman animals are entitled to a certain kind of consideration or treatment. Because such views stress the idea that something is owed or is due directly to these animals, it is common to refer to them as "direct duty" views.

The second possibility, by contrast, locates the ground of moral constraint in some basis other than the animals. Viewed from this perspective, humans owe nothing to other animals, nor do these animals deserve any sort of treatment or consideration. Rather, human freedom should be limited because, for example, human cruelty to other animals will cause humans to treat one another cruelly. Because such views deny that we have duties directly to other animals, while recognizing that other factors should limit our freedom in our dealings with them, they are commonly referred to as "indirect duty" views.

All normative ethical theories, as they address the moral status of nonhuman animals, fall into one or the other of these two classes. That is, either they affirm that we have direct duties to nonhuman animals, or they deny that we have direct duties. Some of the major theoretical options within each class, as these have been developed by ethicists within the history of Western thought, will be considered in what follows.

Abolition, Reform, and Status Quo

As noted earlier, a second important question asks how much our freedom should be limited in our dealings with other animals. Three sorts of options may be distinguished: abolitionist, reformist, and status quo. An abolitionist position argues on behalf of ending human practices that routinely utilize nonhuman animals (for example, as a source of food or as models in scientific research). A reformist position accepts these institutions in principle but seeks in various ways to improve them in practice (for example, by enlarging the cages for animals used in research). A status quo position, unlike the abolitionist position, accepts these institutions in principle and, unlike the reformist position, does not recognize the need to improve them. Representative examples of each outlook and their logical relation-ship to competing normative ethical theories will be explained below.

While the heated, sometimes acrimonious, debate among partisans of abolition, reform, and the status quo captures the attention of the media, far less attention has been devoted to the critical assessment of the competing ethical philosophies, whether of the direct or indirect duty variety. This by itself suggests the degree to which the public debate over "animal rights," broadly conceived, has assumed the greater part of what is most in need of informed, critical reflection. For clearly, whether we should favor the goals of supporters of abolition, reform, or the status quo in practice depends on determining the most adequate account of how we should treat nonhuman animals in theory. It is to a consideration of some of the major options in ethical theory that this entry now turns.

Perfectionism

Aristotle (384–322 b.c.e.) presents the broad outlines of a moral theory that goes by the name "perfectionism." The cornerstone of this theory has a high degree of initial plausibility. Justice, it is claimed, consists in giving to individuals what they are due, and those individuals whose character is morally better (more "perfect") than the character of others prima facie deserve more of what is good in life than do other, less good people. Aristotle's accounts of what makes people morally better and of "the good of man" have helped shape much of Western moral theory. Concerning the latter first, Aristotle accepts the commonplace notion that the good we humans seek is happiness, but he argues that the true happiness we seek is not wealth, fame, or even pleasure in abundance but, rather, the possession and exercise of those virtues (those "excellences") that are uniquely human. Thus happiness, in his view, is characterized as "an activity of the soul in accordance with virtue." Those are happiest who optimally express their humanity in how they live and, in doing so, take pleasure in being the human beings they are.

As for the moral virtues (prudence, justice, courage, and temperance), Aristotle characterizes each as a mean between the extremes of excess and deficiency. A courageous person, for example, is neither foolhardy (an excess) nor cowardly (a deficiency); a courageous person has the right mix of the willingness to take risks and the fear of doing so. Among the intellectual virtues, a detached, contemplative wisdom, wherein one knows eternal truths and in this way shares in that knowledge possessed by the gods, is the highest. In the case of both the moral and the intellectual virtues, finally, the human capacity to reason plays a decisive role. For man is, in Aristotle's view, unique in being "a rational animal," and "the good of man" consists in actualizing, to the fullest extent possible, those unique potentialities that define what it is to be human. Thus, since those are happiest who optimally express their humanity in how they live, those are happiest who exercise their reason optimally.

Because it prescribes the distribution of what is good in life on the basis of one's possessing the favored virtues and, thus, on the basis of degrees of human perfection, perfectionism can—and in Aristotle's hands, does—sanction or require radically inegalitarian treatment of different individuals. In the case of nonhuman animals in particular, perfectionism provides no direct protection. Despite his teaching, in sharp contrast to Descartes's, that these animals share many of the same psychological capacities possessed by humans—including, for example, sensation and desire—Aristotle confidently denies that they share the capacity to reason. Moreover, because in his view the "lesser" exists to serve the interests or purposes of the "greater," Aristotle maintains that nonhuman animals exist for the purpose of advancing the good of human beings. He writes: "Other animals exist for the sake of man, the tame for use and food, the wild, if not all, at least the greater part of them, for food, and for the provision of clothing and various instruments" (Aristotle, "Animals and Slavery," in Regan and Singer, 1976, p. 110; 1989, p. 5). There is no implication here that Aristotle's teachings permit the wanton infliction of pain on nonhuman animals for no good reason. What is clear is that because he recognizes no greater purpose for nonhuman animals than to serve the interests of human beings, Aristotle can recognize only indirect duties in their case. Finally, while many of today's more controversial practices involving human utilization of nonhuman animals, such as factory farming and animal-to-human organ transplants, were un-known in his day, all the available evidence seems to indicate that Aristotle was well disposed to the status quo with respect to the relevant practices current while he was alive.

It is not only nonhuman animals, however, that exist for the sake of those who are more perfect. In general, women do not measure up to Aristotle's standards of "the good of man." "The male is by nature superior, and the female inferior," he writes, "and the one rules, and the other is ruled; this principle, of necessity, extends to all mankind" (ibid.). Moreover, some humans, whether male or female, lack the ability to grasp through reason those truths understood by the more virtuous among us; of such individuals Aristotle writes that they are "slave[s] by nature" (ibid.). And so it is that Aristotle affirms the obvious parallel, given the form perfectionism takes in his hands, between the moral status of human slaves and nonhuman animals: "The use made of slaves and of tame animals is not very different; for both with their bodies minister to the needs of life" (ibid.). Those humans who, because of their superior rationality, are morally more perfect are entitled to make use of those, whether human or not, who lack the virtues defining human perfection.

Few today will publicly embrace Aristotle's perfectionism. Not only does his view of women offend the emancipated gender egalitarianism of our time, but the comfortable elitism and classism that enable him to pronounce some humans "slaves by nature" will find no home among the most basic precepts of contemporary moral, political, and legal thought. The practical implications for humans of the fundamental principle of Aristotelian perfectionism—that those who are lacking in reason exist to serve the interests of those who are most virtuous—is morally offensive. It is one thing to affirm that those people who are more perfect than others prima facie deserve more of what is good in life; it is quite another to maintain that those who are less perfected exist for the sole purpose of ministering to the more virtuous. Moreover, since we cannot rationally defend the exploitation of some humans on the grounds that "by nature" they lack the potential to acquire the virtues possessed by those who exploit them, we cannot rationally defend human exploitation of nonhuman animals by offering an analogous defense—cannot, that is, rationally defend such exploitation by claiming that nonhuman animals "by nature" lack the potential to acquire uniquely human virtues.

Despotism and Stewardship

An alternative to Aristotle's philosophy is rooted in the biblical teaching that the God of Judaism and Christianity gives human beings dominion over nature in general and other animals in particular. As so often happens, however, there is more than one way to interpret the biblical message. Two ways in which human dominion can be understood—despotism and stewardship—will be sketched here.

Despotism teaches that nature in general and the other animals in particular are created by God for the sake of humans, and thus are ordained by the divine creator to serve such myriad human purposes as a source of food and clothing. Nothing within the natural order, save humans, has value in and of itself; what value the natural world possesses is entirely dependent on the extent to which it serves human interests. In this sense, human interests are the measure of all things, at least all things of value. Various biblical passages are cited to confirm the despotic reading, for example, "Then God said, 'Let us make man in our image, after our likeness; and let them have dominion over the fish of the sea, and over the birds of the air, and over the cattle … and over all the earth'" (Gen. 1:26).

Seen in this light, despotism's appeal to what God has ordained provides a reason for human supremacy over nonhuman animals that Aristotle's appeal to what is guaranteed "by nature" seems to lack, and it is a small step from acceptance of the despotic interpretation of human dominion to the conclusion that we owe nothing to nonhuman animals. Thus we find Saint Thomas Aquinas (ca. 1225–1274), for example, urging in words barely distinguishable from those of Aristotle except for their reference to God that it is by "Divine ordinance that the life of animals and plants is preserved not for themselves but for man" (Thomas Aquinas, "On Killing Living Things and the Duty to Love Irrational Creatures," in Regan and Singer, 1976, p. 119; 1989, p. 11). Mindful, moreover, that some biblical passages prohibit cruelty to nonhuman animals, Aquinas firmly places himself within the indirect duty tradition when he maintains that the import of such prohibitions is, for example, "to remove man's thoughts from being cruel to other men, and lest through being cruel to animals one become cruel to human beings" (Thomas Aquinas, "Differences between Rational and Other Creatures," in Regan and Singer, 1976, p. 59; 1989, p. 9).

To the extent that Saint Thomas's philosophy is rooted in the Scripture of the Christian tradition, those who stand outside this tradition are unlikely to be persuaded that God established in nature what nature was incapable of establishing by itself. Even granting biblical underpinnings to one's ethic, moreover, questions arise concerning the accuracy of the despotic interpretation of human dominion. While the Hebrew concept of rada, translated as "having dominion," often is interpreted to mean human despotism over the nonhuman world—an idea that, according to some early critics (White; McHarg), is the root cause of today's environmental crisis—a significantly different interpretation has been proposed by more recent thinkers (Barr; Linzey, 1987; McDaniel; Callicott, 1993).

For rada can be understood as the idea of human responsibility toward and care for a created order that is good independent of the human presence. According to this latter interpretation, commonly referred to as stewardship, humans are given the task of being as loving within the natural order as God was in creating the natural order in the first place. Humans, that is, are to be the loving caretakers of an independently good creation. Because, viewed from the stewardship perspective, the natural world in general, and those nonhuman animals with whom we share it in particular, are good apart from human interests, our duties with regard to these animals emerge as direct duties owed to them rather than indirect duties owed either to other humans or to their creator.

Although when thus interpreted all of creation is seen as having a kind of value that is independent of human interests, the value of nonhuman animals arguably is especially noteworthy. One might note, first, that these animals were created on the same day—the sixth—as were humans (Gen. 1:24–27); that in the original state of perfection, in Eden, humans did not eat other animals (Gen. 1:29); and that, in God's covenant with Noah after the flood (Gen. 9:8–12), animals (but not plants) are included. Using these images, one can argue that the choice we face today is either to continue to move further from the sort of relationship with the animals God hoped would prevail when the world was created or to make daily efforts to recapture that relationship—to journey back to Eden, as it were. Given this latter reading, the practical consequences of a stewardship interpretation of dominion would depart significantly from those favored by the status quo position, just as the goals one would hope to achieve would differ from those advanced by reformists. For if our righteous relationship with the other animals, in our capacities as their caretakers and protectors, is one of nonutilization (they are not to be eaten, not to be worn, etc.), then the stewardship interpretation of human dominion would seem to support an abolitionist ideal.

However these matters are to be settled, the biblical grounding of morality characteristic of both despotism and stewardship places these moral perspectives outside the mainstream of normative ethical theory, at least from the Enlightenment forward, where rigorous, imaginative attempts have been made to ground ethics independently of belief in God and the moral authority of the Bible. One such attempt is contractarianism.

Contractarianism

Among the most influential nontheological political and moral theories, contractarianism has a legacy that reaches at least as far back as Thomas Hobbes (1588–1679) and, among our contemporaries, includes such notable philosophers as John Rawls (1971) and Jan Narveson (1988). Like other theorists united by a common outlook, contractarians often disagree on many of the most fundamental points. It will not be possible to do justice to the rich fabric of disagreement that characterizes proponents of the theories under review.

As its name suggests, contractarianism conceives of morality as a kind of contract into which people (the "contractors") enter voluntarily. For contractarians, morality emerges as a set of mutually agreed upon and enforceable constraints on human freedom, constraints that each party to the contract rationally believes to be in his or her own self-interest. There is, then, according to contractarian theory, nothing that by its nature is morally right or wrong, just or unjust; rather, acts or institutions become right or wrong, just or unjust, as a result of the agreements reached by rational, self-interested contractors. In this sense, all of morality is conventional, and none is natural. Morality is created, not discovered, by human beings.

Both the self-interest that motivates and the rationality that guides the contractors are significant. We are not to imagine that people, as they deliberate about what limits on their freedom they will accept, are motivated by a natural sympathy for the misfortune of others or that they are willing altruistically to accept personal loss so that others might gain. Each contractor is motivated exclusively by his or her self-interest. The conception of individual self-interest each contractor has, moreover, is neither whimsical nor uninformed. Each person asks the same basic question: From the point of view of what is best for me, rationally considered, what limitations on my freedom would I be willing to accept? Morality, understood as rational, enforceable constraints on human freedom, arises when all the contractors jointly agree on the same constraints, not out of sympathy for others or because of altruistic motivations, but because each judges the outcome to be in his or her personal self-interest.

Two fundamentally opposed forms of contractarianism may be distinguished. The first permits the contractors to enter into their contractual deliberations equipped with the knowledge of who they are and what they want out of life, given their individual interests, talents, and hopes. This is the form of contractarianism favored by Hobbes and Narveson, for example. The second, favored by Rawls, requires that the contractors imagine that they lack such detailed knowledge of their individual psychology and circumstances, and instead deliberate about the terms of the contract from behind what Rawls calls "a veil of ignorance." Why Rawls would have recourse to this imaginative point of view will be explained momentarily. First, however, the implications of Hobbesian contractarianism for the treatment of nonhuman animals deserve attention.

Judged on the basis of the interests of these animals, the implications are not particularly salutary. In view of their inability to express these interests and to negotiate with others, nonhuman animals obviously are not to be counted among the potential contractors. Moreover, even while it is true that some things are in the interests of pigs and wolves, for example, the idea that these animals can have an informed understanding of what is in their rational self-interest has no clear meaning. Not surprisingly, therefore, what protection these animals are provided by Hobbesian contractarianism necessarily depends on what interests the human contractarians happen to have in them.

Narveson, for one, cheerfully indicates that this need not be very much (Narveson, "A Defense of Meat Eating," in Regan and Singer, 1989). Because many contractors have a special place in their hearts for companion animals ("pets"), these animals will be treated reasonably well, not because they are entitled to such treatment but because we owe it to their human friends not to upset them (these humans) gratuitously. In the case of most other nonhuman animals, however, including those slaughtered for food or used in research, Narveson finds no good reason to cease and desist. Clearly, then, given Hobbesian contractarianism, all our duties with respect to other animals are indirect duties owed to those human beings who help forge the contract. And just as clearly, considered from a political perspective, one finds little within this version of contractarianism that could mount an abolitionist or a far-reaching reformist approach to how other animals are treated; what one finds instead is a theory well disposed to the status quo while remaining open to modest reforms.

Critics of Hobbesian contractarianism have raised various objections (Regan, 1983). One concerns the possibility of arbitrary discrimination between people—for example, discrimination based on race. If we imagine that a large majority of potential contractors (say, 95%) are white, and the remainder black, then it is not obviously irrational for those who comprise the majority to exclude members of the minority from negotiating the contract; perhaps the majority might even agree to keep the minority in bondage, as chattel slaves, the better to advance the rational self-interests of those individuals comprising the majority. That such an arrangement would be unjust seems too obvious to need a supporting argument. And (for Hobbesian contractarianism) there's the rub. For since what is just and unjust is created by the agreements reached by the contractors, there is, within this form of contractarianism, no theoretical grounding for the evident injustice involved in excluding the minority from participating. The theory, that is, not only fails to illuminate why such discrimination is unjust, but it also seems to deprive us of the means even to raise this objection. If a moral theory is so fundamentally flawed when it comes to how human beings, given their differences in skin pigmentation, should be treated, it is unclear how it can be any nearer the truth when it comes to how nonhuman beings, given their species differences, should be treated.

Rawls's introduction of the veil of ignorance, mentioned earlier, can be interpreted as his attempt to preserve the spirit of Hobbesian contractarianism while departing importantly from the letter. Rawls invites would-be contractors to imagine themselves in what he calls the "original position," in which, because they deliberate from behind the veil of ignorance, they do not know when they will be born or where, whether they will be rich or poor, of exceptional intelligence or below average, male or female, Caucasian or non-Caucasian. The question now to be asked, by each of the contractors, is what limits on human freedom each would accept, in the face of such profound ignorance concerning such details.

The full scope of Rawls's answer need not concern us. Only two points are of particular importance here. The first concerns how Rawlsian contractarianism improves on Hobbesian contractarianism when it addresses the issue of discrimination based on race. Hobbesian contractors, as noted above, can have a self-interested reason for accepting such discrimination, given that they know they belong to a racial majority. Rawlsian contractors, in contrast, lack such a reason since, for all they know, they might be one of the minority. In this respect, Rawlsian contractarianism seems to represent a notable improvement over Hobbesian contractarianism.

Despite its apparent strengths in response to issues involving arbitrary discrimination, Rawls's account of the moral status of nonhuman animals seems to fail to live up to its own standards (Van DeVeer). While the imaginary contractors behind the veil of ignorance are denied detailed knowledge about their individual interests and circumstances, and thus do not know whether, say, they will be male or female, black or white, Rawls does permit them to know that they will be born as human beings. To allow knowledge of this detail, however, seems to prejudice the case against nonhuman animals from the start. Granted, rational, self-interested contractors, making choices from behind the veil of ignorance, will negotiate direct duties to human beings and indirect ones to nonhumans, if they know they will be born human. But this only shows that these contractors will discriminate against these animals if they are provided with an arbitrary reason for doing so. In short, neither Hobbesian nor Rawlsian contractarianism seems to offer a reasonable basis on which to ground the only duties each recognizes in the case of nonhuman animals: indirect duties.

Kantianism

A final example of an indirect duty view is provided by the great Prussian philosopher Immanuel Kant (1724–1804). In some respects Kant's moral philosophy regarding the treatment of nonhuman animals is an amalgam of Aristotle's and, stripped of its appeals to God, Aquinas's. In concert with both, Kant emphasizes rationality as the defining characteristic of being human and, echoing Saint Thomas, objects to cruelty to animals because of the deleterious effect this has on how humans are treated. "He who is cruel to animals," Kant writes, "becomes hard also in his dealings with men," whereas "tender feelings towards dumb animals develop humane feelings towards mankind" (Kant, "Duties in Regard to Animals," in Regan and Singer, 1976, p. 123; 1989, p. 24).

Despite these historical echoes, Kant's moral philosophy is in many ways highly original. Of particular note is his thesis that humanity exists as an "end in itself." Kant does not attempt to prove this thesis by appeal to some more basic principle; rather, it is set forth as a postulate in his system. In this capacity it places humans and other rational, autonomous beings in a unique moral category that distinguishes them, as "persons," from everything else that exists. Like Aristotle and Aquinas before him, Kant views the rest of the natural order as existing to serve human interests. In particular, animals, in his words, exist "merely as a means to an end. That end is man" (ibid.). Thus, whereas in Kant's view we are morally free to use other animals as we wish, subject only to the injunction to avoid cruelty, we are not morally free to treat human beings in a comparable fashion. Because humans exist as ends in themselves, we are never to treat them merely as means, Kant argues, which is what we would be doing if we treated them as we treat other animals (for example, if we raised humans as a food source). An abolitionist, a radical reformist, Kant is not. Provided only that we are not cruel in our treatment of nonhuman animals, we do nothing wrong when we treat them as we do.

A common objection against Kant's position is the argument from marginal cases (Regan, 1983; for criticism of this argument, see Narveson, 1977). All humans, Kant implies, exist as ends in themselves. To restrict this supreme moral value to humans among terrestrial creatures is not arbitrary, Kant believes, because humans, unlike the other animals, are unique in being rational and autonomous. However, not all humans are rational and autonomous. Those who are mentally enfeebled or deranged, for example, lack these capacities. Are these humans nevertheless ends in themselves? If Kant's answer is affirmative, then it is not the presence of rationality and autonomy that ground this supreme moral value; if, on the other hand, Kant's answer is negative, then it follows that these "marginal" human beings do not exist as ends in themselves, in which case it would seem that they, no less than other animals, may be treated as mere means. Because one assumes that this latter consequence would be seen by Kant to be morally grotesque, it seems fair to assume that he would want to avoid it; but he can do so, it seems, only by accepting the view that individuals who are neither rational nor autonomous nevertheless exist as ends in themselves, a view that undermines his confident assertion that nonhuman animals, deficient in reason and autonomy, exist "merely as means to an end," the end being "man."

Utilitarianism

The pioneering work of the nineteenth-century utilitarians Jeremy Bentham (1748–1832) and John Stuart Mill (1806–1873) represents a significant departure from the Aristotelian legacy we find in Kant's moral theory. Bentham, referring to nonhuman animals, writes, "The question is not, Can they reason? nor, Can they talk? but, Can they suffer?" (Bentham, "A Utilitarian View," in Regan and Singer, 1976,p. 130; 1989, p. 26). The possession of sentience (the capacity to experience pleasure and pain), not the possession of rationality, nor autonomy, nor linguistic competence, entitles any individual to direct moral consideration; and it is the possession of this particular capacity, in Bentham's and Mill's view, that creates in humans the direct duty not to cause nonhuman animals to suffer needlessly. We owe it to these animals themselves, not to those humans who might be affected by what we do, to take their (the nonhuman animals') pleasures and pains into account and, having done so, to ensure that we never make them suffer without good reason.

Both Bentham and Mill give a utilitarian interpretation of what such a good reason might be. Utilitarianism, roughly speaking, is the view that our duty is to perform that act that will bring about the best consequences for all those affected by the outcome. For value hedonists like Bentham and Mill, who recognize only one intrinsic good, pleasure, and only one intrinsic evil, pain, the best consequences will be those that include the greatest possible balance of pleasure over pain. A good reason for permitting animal suffering, then, is that such suffering is a necessary price to pay in bringing about the best consequences, all considered. How much of the spirit of reform, abolition, or the status quo happens to characterize individual utilitarians depends on how much animal suffering is judged to be necessary. Bentham opposes hunting, fishing, and the baiting of animals for sport, for example, while Mill's name is to be found among the earliest contributors to England's Royal Society for the Prevention of Cruelty to Animals. But neither Bentham nor Mill aligns himself with the cause of antivivisection, and both are lifelong meat eaters. So reformers they are, but abolitionists they are not. Even so, in their time, and given the broader social context in which they lived, they were seen by many of their contemporaries as radicals, if not extremists.

The degree to which utilitarians can differ over important practical matters is illustrated in our time by Peter Singer and R. G. Frey. Singer is justly famous for his seminal 1975 book, Animal Liberation, while Frey has written two books (1980, 1983) and many essays devoted to the issues under review. The two philosophers, while agreeing on some of the most fundamental points in ethical theory, disagree on many of the most important consequences each believes follow from the application of utilitarianism, including how nonhuman animals should be treated. For example, in Animal Liberation Singer advocates vegetarianism, on moral grounds; Frey disagrees, appealing to the same grounds in his Rights, Killing, and Suffering: Moral Vegetarianism and Applied Ethics (1983). It will be useful to explain how such profound disagreements can arise between partisans of the same moral philosophy.

By its very nature, utilitarianism is a forward-looking moral theory. The consequences of our actions, and the consequences alone, determine the morality of what we do. As such, utilitarians will reach opposing judgments about what is right and wrong if they have opposing views of what the consequences of a given act will be. In the case of vegetarianism in particular, utilitarians like Singer believe that, taking everyone's interests into account, and counting equal interests equally, the consequences that flow from abstaining from animal flesh will be better than if people continue to include animal flesh in their diets; Frey, however, believes that the consequences of a vegetarian diet are not sufficiently better so as to impose an obligation on us to become vegetarians. It is, then, factual disagreements over what the future might hold that underlie the type of moral disagreement separating Singer and Frey on the issue of vegetarianism.

Some critics of utilitarianism (e.g., Clark) argue that the apparently unresolvable impasse created by Singer's and Frey's application of utilitarian theory to the particular case of vegetarianism illustrates a major weakness in utilitarian theory in general. Because so much—indeed, because everything—depends on our ability to know what will happen in the future, and in view of the limitations of human knowledge in this regard, utilitarianism, these critics maintain, reduces moral judgment to guesswork about what might or might not occur.

Despite this problem, utilitarianism may seem to be a congenial theory for those who utilize nonhuman animals in animal model research. The most common justification of such research consists in appealing to the improvements in human health and longevity to which this research allegedly has led; and while researchers may recognize the need to look for alternatives to the animal model, lest these animals be used unnecessarily, it seems clear that the moral justification they offer is utilitarian. (For dissenting voices regarding the human benefits of such research, from the perspective of the history of medicine, see McKinlay and McKinlay; for epistemological concerns, see LaFollette and Shanks). Part of the enduring greatness of Animal Liberation lies in Singer's relentless documentation of how much of this research prima facie fails to meet the utilitarian standard favored by researchers themselves. No less important is the way Singer exposes a prejudice that he, following Richard Ryder (1975), denominates "speciesism," and that he characterizes as "an attitude of bias in favor of the interests of members of one's own species and against those of other species" (Singer, 1990, p. 6). Research scientists, Singer believes, frequently offer at best half a utilitarian justification of their work: Human interests are considered; those of nonhuman animals are not. To be consistent, the interests of both must be counted, and counted equitably. It is Singer's considered judgment that few researchers are consistent in this regard.

Frey, too, examines the lack of moral consistency among researchers ("Vivisection, Morals, and Medicine," in Regan and Singer, 1989). Given any reasonable view about the richness and variety of psychological life, it is unquestionably true, Frey believes, that the psychological life of nonhuman primates, or even that of a cat or a dog, is richer and more varied than the psychological life of some human beings (a child born with only the stem of the brain, for example). Thus, if the moral defense of animal model research is supposed to lie in the good results allegedly produced by using these animals, then a similar defense for utilizing marginal humans is at hand. To be consistent in their utilitarianism, therefore, Frey believes that researchers should be willing to conduct their studies on marginal humans—a finding researchers are unlikely to welcome. Frey is unperturbed, insisting that researchers cannot have it both ways, using utilitarian modes of thinking when they believe it justifies their practice of using other than human animals in their studies, only to discard utilitarianism when its implications for the selection of marginal humans as research subjects are made manifest.

Whatever form utilitarianism takes, one of the principal objections its advocates face centers on questions of justice (Lyons). What limits, if any, can utilitarianism recognize on how future good is to be obtained? The theory seems to imply that good ends justify whatever means are necessary to achieve them, including means that are flagrantly unjust. Classic examples include situations in which the judicial execution of the innocent is sanctioned on the grounds that others will be deterred from committing similar offenses. Here, critics concede, good consequences are brought into being, but the means used to secure them are reprehensible because they are unjust.

Utilitarians have replies to this and similar lines of criticism that go beyond the scope of the present entry (Brandt). Suffice it to say that among those philosophers who are not utilitarians, many dissociate themselves from utilitarianism because they believe that respect for the rights of the individual is a principle that should not be compromised in the name of achieving some greater good for others. Not surprisingly, perhaps, a position of this kind, one that prohibits the use of nonhuman animals in the name of advancing the general human welfare, has been advanced (Regan, 1983). Though not the only possible theory of animal rights (see, e.g., Rollin, 1981, 1989), this particular theory (the "rights view") can be seen as an attempt to blend certain features of utilitarianism and Kant's theory.

The Rights View

Kant, it will be recalled, recognizes only indirect duties to nonhuman animals; we humans are not to be cruel to animals, for example, not because we treat them wrongly by our cruel treatment but because cruelty to animals can lead people to be cruel to one another. By contrast, utilitarians from Bentham to Singer recognize direct duties to nonhuman animals; they believe that there are certain things we owe to these animals, apart from how humans will be effected. On this divisive issue the rights view sides with utilitarians against Kantians: Nonhuman animals are of direct moral significance; we have direct duties in their case.

In a second respect, however, the rights view sides with Kantians against utilitarians. Utilitarians believe that duty is determined by the comparative value of consequences; the right thing to do is what causes the best results. Kant and his followers take a decidedly different view: What is right does not depend on the value of consequences, it depends on the appropriate, respectful treatment of the individual—in particular, whether humans are treated as ends, not merely as means. In this regard, the rights view is cut from Kantian, not utilitarian, cloth. What is right depends not on the value of consequences but on the appropriate, respectful treatment of the individual, including individual nonhuman animals. Thus, the fundamental principle of the rights view (the respect principle) is Kantian in spirit: We are always to treat individuals who exist as ends in themselves (those who have "inherent value") with respect, which means, in part, that we are never to treat them merely as means.

One problem the rights view faces concerns which nonhuman animals possess value of this kind. Like other line-drawing issues ("Exactly how tall do you have to be to be tall?" "Exactly how old do you have to be to be old?"), this one has no precise resolution, in part because the criterion for drawing the line is imprecise. The criterion the rights view proposes is that of being the subject of a life, a criterion that specifies a set of psychological capacities (the capacities to desire, remember, act intentionally, and feel emotions, for example) as jointly sufficient. At least some nonhuman animals (e.g., mammals and birds) arguably possess these capacities, thus are subjects of a life, and thus, given the rights view, are to be treated as ends in themselves. (For criticism, see Frey, 1980).

Such a view, for obvious reasons, has massive political, social, and moral implications concerning how these animals ought to be treated. From an animal rights perspective of this kind, the abolition of human exploitation of these animals, whether on the farm, at the lab, or in the wild—not merely the reform of these practices, and certainly not approval of the status quo—is what duty requires.

Line-drawing issues aside, the rights view faces daunting challenges from other quarters. One concerns the idea of inherent value. Some critics (e.g., Sapontzis) allege that the idea is "mystifying," meaning that it lacks any clear meaning. Advocates of animal rights reply that the notion of inherent value is no less "mystifying" than Kant's idea of end in itself. As applied to human beings, Kant's idea of end in itself attempts to articulate the cherished belief that the value or worth of a human being is not reducible to instrumental value—not reducible, that is, to how useful a human being happens to be in forwarding the interests or purposes of other human beings. Neither John Doe nor Jane Doe, in Kant's view, exists as a mere resource relative to what other people want for themselves, and to treat the Does as if their value—their worth or dignity—consists merely in their resource or instrumental value for others is morally wrong. All that the rights view alleges, then, is that to be consistent, the same moral judgment must be made in those cases where nonhuman animals that are subjects of a life are treated in a similar fashion.

Another set of challenges alleges that the philosophy of animal rights, if acted upon, would lead to catastrophic consequences, either to human interests in particular or to the community of life in general. Concerning the former challenge, some critics argue that human health and longevity would be seriously harmed if, as the philosophy of animal rights requires, nonhuman animals ceased to be used as models of human disease (see C. R. Gallistel, "The Case for Unrestricted Research Using Animals," in Regan and Singer, 1989; and Cohen). Several responses seem apposite.

First, given the massive allocation of public monies that fund such research, it needs to be asked whether abandoning reliance on the whole-animal model really is contrary to what is in the collective best interests of human beings. Some (e.g., Sharpe) argue that customary reliance on this well-entrenched scientific methodology retards the development of alternative methodologies that would be more useful in understanding and curing major human diseases; in addition, these critics insist that humans would benefit more if the dominant focus of biomedical research were shifted away from curing disease to preventing it, a goal that is more efficiently advanced, these critics allege, by methodologies other than the use of the whole-animal model.

Second, recall one of the fundamental objections raised against utilitarianism: Just as one does not justify the violation of a human being's rights because doing so will benefit others, so one does not justify the violation of the rights of nonhuman animals on similar grounds. More generally, some gains others might obtain may be ill-gotten, and they are ill-gotten if the price of obtaining them involves the violation of another's rights. Thus, even if it is true that humans stand to lose some benefits if animal model research is abandoned, this by itself does not constitute a telling moral objection to the abolitionist implications of the philosophy of animal rights, assuming that these animals, like humans, have the right to be treated as ends in themselves.

Concerning the second line of criticism—the one alleging that acting on the philosophy of animal rights would have catastrophic implications for the community of life in general—the principal objection may be summarized as follows. Predatory animals obviously live off the death and flesh of their prey. Because prey animals have the right to be treated with respect, according to the rights view, critics (e.g., Callicott, 1980; Sagoff) allege that it follows that we should intervene to stop predatory animals in their natural depredations. However, if we were to do this, there would be no check on the balance that exists in nature between predators and preys; instead, the population of prey animals would explode, and this would have the effect of irreparably damaging the balance and sustainability of life forms within the larger life community.

Advocates of the philosophy of animal rights have a number of possible replies to the predation problem, the principal one of which is the following. Situations can and do arise where the right thing to do is to come to the assistance of another, whether the potential victim is a human or a nonhuman animal. However, in these situations the potential victim not only is at risk of serious injury but also is less than capable of mounting a defense. Thus, an elderly woman who is attacked by a psychotic killer, or a puppy who is being tormented by children, merits our intervention. But the predator–prey relationship seems to bear little resemblance to such cases. Most prey animals, most of the time, are perfectly capable of eluding their predators without anyone's assistance. Thus it would seem to be human arrogance, not informed responsibility, that would lead humans to believe that because animals in the wild have rights, we are duty bound to "police" nature. From an animal rights perspective, we have no general duty to intervene in predator–prey relations; that being so, the catastrophic environmental costs alleged to be implied by acting on the rights view seem to be more in the nature of fiction than of fact. (For a different response to the predation problem, see Sapontzis.)

Deep Ecology

Despite the significant differences separating the philosophy of animal rights and other, more traditional moral theories, such as Kant's, there are important similarities. For example, like Kant's theory, the philosophy of animal rights recognizes the noninstrumental value of the individual; and animal rights philosophy, as is true not only of Kant's theory but of utilitarianism as well, articulates an abstract, universal, and impartial fundamental moral principle—abstract because the respect principle enjoins us to treat others with respect, without regard to time, or place, or circumstance; universal because the respect principle applies to everyone capable of making moral decisions; and impartial because this principle does not favor some individuals (e.g., family members or companion animals) over others. Some contemporary moral philosophers find this approach to ethics archaic; among these critics, some of those who classify themselves as deep ecologists (see, in particular, Devall and Sessions) command a growing audience. (For a more systematic and in some ways different version of deep ecology, see Naess. For importantly different approaches to environmental ethics, see Taylor; Rolston; Callicott, 1980.)

Both traditional moral theories and the philosophy of animal rights are doubly to be faulted, according to Devall and Sessions—first, because these moral outlooks offer an overly intellectualized account of the moral life, and second, because they perpetuate the myth of the moral preeminence of the individual. Considering this latter charge first, Devall and Sessions argue that the concept of the isolated, atomistic individual, which arises out of the anthropocentric traditions of Western philosophy, is false to the facts of all life's embeddedness in the larger life community. People are not independent bits of mind existing by themselves; they are enmeshed in networks of relationships that bind them both to their evolutionary past and to their ecological present. Expressed another way, humans do not stand "above" or "apart from" nature; they stand "within" nature. And the natural world does not exist "for us," as a storehouse of renewable human resources (a view that is symptomatic of a "shallow" view of humanity's relationship to nature); we are inseparable from the natural environment (a view that indicates a "deeper" understanding of what it means to be human).

Thus, acceptance of the illusory concept of the isolated individual, existing outside the natural order, has done, and continues to do, incalculable damage to those who seek self-understanding. So long as we carry out this quest with a fundamentally flawed preconception of our place in the larger scheme of things, the longer we search, the less we will understand. As for the charge that traditional moral theories overintellectualize the moral life, Devall and Sessions argue that the moral life should be viewed as primarily experiential, not inferential, a life that is characterized by our coming to experience certain values in the concrete particularities of day-to-day life, rather than by apprehending abstract, universal, impartial moral principles by means of our rational powers.

Among those values to be found in the concrete particularities of day-to-day life, some involve other animals; and although deep ecologists have not written extensively on some of the most pressing practical issues, the general disdain these thinkers display toward reductionist science and industrial societies' technological domination of the natural world suggests that they would be strong reformists, at a minimum, in response to such practices as factory farming and animal model research. In the case of sport and recreational hunting, however, Devall and Sessions not only find nothing wrong, they applaud the practice. In pursuit of their prey, hunters tap into natural means whereby, through the act of killing, they can obtain greater self-understanding. Viewed in this light, Devall and Sessions seem to understand our duties with respect to animals as indirect duties limited by the overarching quest for self-knowledge. While, therefore, deep ecologists like Sessions and Devall can be counted upon to add their voices to those of reformists and abolitionists in some cases, they emerge as defenders of the status quo in others.

Ecofeminism

Ecofeminists, not just advocates of the rights view, are among those contemporary moral philosophers who differ significantly with deep ecologists. Like other isms, ecofeminism is not a monolithic position (see Adams; Diamond and Orenstein; Warren; Gaard); instead, it represents a number of defining tendencies, including in particular a principled stance that puts its advocates on the side of those who historically have been victims of oppression. For obvious reasons, women are pictured as among the oppressed, but the scope of ecofeminism's concern is not limited to women. The same ideology that sanctions oppression based on gender, ecofeminists maintain, also sanctions oppression based on race, class, and physical abilities, for example; moreover, beyond the boundaries of our species, this same ideology, ecofeminists believe, sanctions the oppression of nature in general and of nonhuman animals in particular.

In a number of fundamental ways, ecofeminism's diagnosis of the ideology of oppression resembles deep ecology's diagnosis of the deficiencies of traditional moral theory. As is true of the latter, ecofeminism challenges the myth of the isolated individual, existing apart from the world, and instead affirms the interconnectedness of all life. Moreover, no less than deep ecologists, ecofeminists abjure the overintellecutalization of the moral life characteristic of traditional moral theories, with their abstract, universal, and impartial fundamental principles. But whereas deep ecologists locate the fundamental cause of moral theory gone awry in anthropocentrism (human-centeredness), ecofeminists argue that it is androcentrism (male-centeredness) that is the real cause.

Nowhere is this difference clearer than in the case of sport or recreational hunting. Devall and Sessions celebrate the value of this practice as a means of bonding ever more closely with the natural world, of discovering "self in Self"; ecofeminists, by contrast, detect in the hunt the vestiges of patriarchy—the male's need to dominate and subdue (Kheel). More fundamentally, there is the lingering suspicion that deep ecologists continue to view the value of the natural world instrumentally, as a means to greater self-awareness and self-knowledge. In this respect, and despite appearances to the contrary, deep ecology does not represent a "paradigm shift" away from the anthropocentric worldview it aspires to replace.

Ecofeminists believe they offer a deeper account of the moral life than do deep ecologists, one that goes to the very foundations of Western moral theorizing. The idea of "the rights of the individual" is diagnosed as a symptom of patriarchal thought, rooted in the (male) myth of the isolated individual. Morally, a "paradigm shift" occurs when, in place of assertions of rights, we freely, lovingly choose to take care of and assume responsibility for those who are victims of oppression, both within and beyond the extended human family, other animals included. Writing for the growing number of ecofeminists, Josephine Donovan states:

Natural rights and utilitarianism present impressive and useful arguments for the ethical treatment of animals. Yet, it is also possible—indeed, necessary—to ground that ethic in an emotional and spiritual conversation with nonhuman life forms. Out of a woman's relational culture of caring and attentive love [there] emerges the basis for a feminist ethic for the treatment of animals. We should not kill, eat, torture, and exploit animals because they do not want to be so treated, and we know that. If we listen, we can hear them. ("Animal Rights and Feminist Theory," in Gaard, p. 185)

Thus, whereas the grounds for practical action offered by ecofeminists differ fundamentally from those favored by the rights view, and despite the foundational gulf that separates these two theories, both philosophies arguably have the same abolitionist practical implications.

Conclusion

The "animal rights debate," broadly conceived, is more than a contest of wills representing professional, economic, and ethical concerns; it is also a divisive, enduring topic in normative ethical theory (Vance). Until comparatively recently, discussions of the moral status of nonhuman animals had all but disappeared from the work of moral philosophers. (For a historical overview, see Ryder, 1989.) Beginning in the 1970s (Godlovitch et al.; Singer, 1975; Linzey, 1976; Clark), however, we have witnessed a historically unprecedented outpouring of philosophical and theological interest in exploring the moral ties that bind humans to other animals, and there is every indication that this interest will intensify in the coming decades. The moral theories of philosophers are not the stuff of politics; still, the contributions philosophers make can help shape the political debate by clarifying the major theoretical options available to an informed public.

Principal among these options are those that have been canvassed here: perfectionism, despotism and stewardship, contractarianism, Kantianism, utilitarianism, the rights view, deep ecology, and ecofeminism. Doubtless other options will evolve as the discussion continues (Garner). Among these options, two in particular—utilitarianism and the rights view—have offered the most systematic accounts of those duties owed directly to nonhuman animals. It will be instructive, before concluding, to highlight some of the important practical differences, particularly as these pertain to animal model research, that flow from these competing philosophies.

Because utilitarianism is committed to reducing the total amount of suffering in the world, its proponents must be prepared to recognize the moral legitimacy of some research on nonhuman animals. Even Peter Singer, contemporary utilitarianism's most forceful critic of such research, has conceded this possibility (Singer, 1993). Moreover, utilitarians must be similarly well disposed to the activities of animal care and use committees (Singer has served as a member of such a committee), provided that these committees conscientiously work to eliminate unnecessary animal suffering. Legislative attempts to improve the well-being of animals, whether in laboratories or on the farm, find support among utilitarians. Viewed in these respects, utilitarianism offers a philosophical basis for those who would reform the ways in which nonhuman animals are utilized by humans; what it does not offer is a categorical condemnation of this utilization. For this reason utilitarianism is congenial to those individuals and groups working to advance animal welfare—who accept, that is, the morality of human utilization of nonhuman animals in principle but who seek to improve it, by making it more humane, in practice.

The rights view has a different perspective on such matters (Francione and Regan). This philosophy is opposed to human utilization of nonhuman animals in principle and seeks to end it in practice. Its practical implications are abolitionist, not reformist. Because those nonhuman animals who exist as ends in themselves are never to be treated merely as means, it is wrong to experiment on them in the name of advancing the well-being of others. Moreover, to the extent that animal care and use committees and reformist legislation help to perpetuate social acceptance of human exploitation of these animals, whether on the farm or in the laboratory, advocates of the rights view will—or, to be consistent, should—withhold their support. What animal rights advocates can consistently support are incremental steps that put an end to certain practices within the larger context of animal exploitation—for example, legislation that would prohibit the use of nonhuman animals in cosmetic testing and in drug addiction experiments, and the creation of policies that end compulsory vivisection and dissection in the classroom (Francione and Charlton). When, as can often happen, utilitarians deem such practices unjustified because they cause gratuitous animal suffering, these two conflicting normative ethical philosophies—utilitarianism and the rights view—can speak with one voice. And when this happens, their potential political power is greater than the sum of its parts.

No one can predict which of the tendencies examined above—reform, abolition, or the status quo—will prevail in the coming years. Some positions (e.g., the rights view and ecofeminism) call for fundamental social change; others (e.g., Aristotelian perfectionism and Kant's view) call for much less. To the extent that people act because of their beliefs, the future of how humans treat other animals depends on what we humans believe the latter to be and how we think they should be treated. Because what we should do in practice depends on understanding what we ought to do in principle, our ability to give an appropriate response to the practical issues constituting the animal rights debate, broadly conceived—from whether we ought to be vegetarians to whether we should continue to use nonhuman animals in biomedical research—depends on our ability to make an informed, rational choice among normative ethical theories. In this respect, while a fair consideration of such theories may not be the end-all, it can make some claim to being at least part of the begin-all of a commitment to seek understanding and truth in these troubled waters.

thomas regan (1995)

bibliography revised

SEE ALSO: Animal Research and Rights; Endangered Species and Biodiversity; Environmental Ethics; Pain and Suffering; Veterinary Ethics; and other Animal Welfare and Rights subentries

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