Introduction
As veterinary ethics matures, it is important that veterinarians engage with ethical theories, and the increasingly large literature on animals' moral standing, so that our decisions are defensible and maintain social credibility. This paper briefly explores some major theoretical options and the question of animals' moral standing.
Virtue Theories
Virtue theories concentrate primarily not on our obligations or how we should conduct ourselves, but rather on the kind of person we should be and the kind of character we should cultivate. A virtue can be defined as "a commendable trait of character manifested in habitual action" (Rachels 2010, p. 160). Examples of virtues are benevolence, compassion, fairness and patience. Virtue theories typically provide some further definition of the virtues in addition to naming them. For example, we might say, following Aristotle, that courage is a mean (or midpoint) between cowardice and foolhardiness. In addition, we need to have some idea of how a virtuous person would act, and why.
The main attraction of virtue theories is that they can account for the importance of moral motivation. We often think that living morally isn't just about what we do; it's also about why we do it. In addition, there are some cases where a certain kind of action seems wrong, even though it does not violate any moral principles of conduct. In some of these situations, we can account for the wrongness of the action by appealing to virtue.
Some of the most common language that we use to talk about animals and ethics is virtue-based. We say, for example, that we ought not to be cruel to animals and that we ought to be kind to them. Similarly, the word "humane," which appears for example in the American Veterinary Medical Association's "Animal Welfare Principles," has psychological connotations to it. But neither the concept of "kind" nor "humane" treatment seems to have received much analysis as these terms are applied to animals.
This brings us to some problems with virtue theory. First, having the right motivation is not enough - we can imagine a person doing a terrible thing to another even though they have the right motives. Second, when thinking about why a virtue is a virtue, it would seem that it is because a virtuous person acts a certain way or brings a certain result about - suggesting that in most cases, it is the outcome of an action, or the action itself, that is morally primary - not the virtue. This point applies equally to why a particular virtue leads to a certain action.
Deontological Theories
The word "deontological" roughly translates into "duty-based," and deontological theories tend to define the moral life in terms of duties, rules or principles that we should follow - in contrast to virtue theories, which focus primarily on our character. An example of such a deontological principle is "do not cause harm to others without their consent." Rights-based theories also fall under the umbrella of deontological theories, since rights lay out entitlements that people have (e.g., the right not to have our body invaded against our will), and these rights generally correlate to other persons' obligations to respect our rights.
There are a number of theories that we can classify as deontological. As already mentioned, natural rights theories qualify as deontological. Moral and legal rights are well-enshrined in Western societies, so these should be familiar. Proponents of rights may or may not base their ascription of rights on more fundamental arguments; sometimes the basis for rights is simply that it is a "considered moral judgment" that we have them. As concerns animals, a notable proponent of a rights theory is Tom Regan, who elaborated quite a strong theory of animal rights that proscribed almost all harms to animals. But one can also recognize animal rights in a less strong sense - it all depends on which rights we think animals have.
Another type of deontological theory is social contract theory, sometimes called contractarianism. The classical version of this moral theory makes the basis of morality a hypothetical contract between rational actors. The content of morality is those rules that rational, self-interested people would agree to for their mutual benefit. The reason why we should obey the rules is that doing so serves our interest in the long run. For example, though it might sometimes be advantageous to us to steal another person's property, we would rather that our property not be stolen, and the best way for us to secure this protection is to agree to a rule to respect others' property in return for having them respect ours.
A third type of deontological theory, which is somewhat related to social contract theory, is Kantianism, named after the famous Prussian philosopher Immanuel Kant. Kant made the basis of morality "good willing," and he proposed that an action is not moral unless it conforms to what he called the "categorical imperative" (CI). There are different forms of the CI; arguably the best-known is that which holds that an action is not moral unless the person who proposes to do it could will it as a universal law. For example, we may wish to lie sometimes, but we would not validly will lying as a universal law, since this would mean that everyone would go around lying, which would destroy the fabric of civilization (amongst other things). Another form of the CI tells us that we should always treat other people as ends in themselves, and never use them merely as a means to our own end.
In their classical forms, social contract theory and Kantianism only held that rational agents belong in the sphere of moral consideration. This would exclude animals, but also non-rational humans. More modern forms of these theories have some additional features that would extend consideration to non-rational humans and animals. The key feature of these theories that are retained in modern versions are the idea of fairness, the idea of trying to universalize our actions when justifying them morally, the idea that there are limits to what we can do to others in seeking our own benefit, and the idea that sometimes morality requires that we adhere to certain rules, even when breaking the rules might have better consequences for everyone. We can retain these ideas without holding that only rational agents have moral standing.
Many if not most people believe that when it comes to acting morally, there are certain things that you just should not do. For example, we could enroll children in a biomedical research experiment that would produce great benefit for society, but which would inflict terrible debility or even death upon the children. Even though the overall amount of good might outweigh the bad, most people think that it would be wrong to do this - that we have an obligation not to harm the children that supersedes any benefit that society might derive from the experiment. The main attraction of deontological theories is their ability to preserve and account for such intuitions. However, deontological theories can also be criticized for being too rigid in their adherence to rules.
Consequentialist Theories
Consequentialist theories also conceptualize the moral life primarily in terms of how we conduct ourselves. But whereas deontological theories tend to elaborate duties or rules that one should follow - e.g., "Don't lie," "Don't murder," etc. - consequentialist theories define moral conduct in terms of the consequences that would follow from acting a certain way. The most famous consequentialist theory is utilitarianism. In its classical form, utilitarianism is guided by the principle of utility, which holds that the morally right action is that which best maximizes goodness over badness, as compared to alternative courses of action, for all persons concerned - not just you (the agent). So, for example, while a deontological theory might tell us that we should rarely or never lie, even when lying could bring about good consequences, a utilitarian would base their answer on whether lying would or would not bring about good consequences. If telling a lie would bring about worse consequences than not lying, then you should not tell the lie. But if lying would bring about the best consequences, then you should do it.
The most classical form of utilitarianism is act utilitarianism, which holds that we should subject each and every choice we make to the principle of utility. However, this can get pretty taxing, so some utilitarians opt instead for a version of the theory called rule utilitarianism, which holds that we should follow rules that generally maximize utility. Rule utilitarianism looks similar to deontological theories, but the reason for following the rules is different, and a rule utilitarian only has a reason to follow a rule if the rule will maximize utility - you can break the rule if not. The main attraction of utilitarianism is the idea that we ought to promote the overall good, and that our moral decisions should be sensitive to what will actually happen as a result of our actions. The main criticism of utilitarianism is that it can potentially justify inflicting severe harms on others if this best serves the overall good.
Animals' Moral Considerability
In addition to a general framework for thinking through ethical issues, we need to have some idea of where nonhuman animals fit with respect to humans. We want to know how much moral weight or importance we should give to animals' interests - that is, to the things that make their lives go well or poorly (e.g., their interest in avoiding pain). There are roughly three options here. First, we may say that animals are due no moral consideration. This means that animals' interests do not count directly in moral decision-making. However, animals' interests may still count indirectly because how we treat animals affects human interests. For example, being sadistically cruel to animals may make a person more likely to perpetrate violent crimes against other humans, and so a prohibition on cruelty to animals could be justified even on this "no moral consideration" view by reference to human interests. Still, a "no moral consideration" would place very few restrictions on how we treat animals - for the most part we can do what we want with them, regardless of how much harm this causes to the animals.
At the other end of the spectrum is an equal moral consideration view, which says that we should give the same amount of moral consideration or weight to animals' interests as we give to comparable human interests. So, for example, we should give as much weight to an animal's interest in avoiding suffering as we give to a human's interest in avoiding suffering. While philosophers still debate some aspects of how we should interpret the idea of equal moral consideration, there is general agreement that accepting this principle would require radical transformations in how we treat animals. For example, most invasive animal research would be immoral, and it is also likely that raising and killing animals for food would also be immoral.
Finally, there is an unequal moral consideration view, which holds that animals are direct objects of moral concern whose interests matter, but that human interest normally matter more. There are different versions of this kind of view, but one possibility is that moral standing is a function of cognitive, affective and social complexity, where the more complex an organism is in these respects, the higher its moral standing. In this paradigm humans would stand atop the moral hierarchy (for now), with some nonhuman animals (e.g., chimpanzees) deserving slightly less but still significant moral consideration, and the level of moral consideration decreasing as we move down the phylogenetic scale (DeGrazia 2002).
Given these options, which is the most defensible? Until very recently in Western history, most philosophers have held that animals do not deserve any moral consideration at all. Most persons today do not seem to hold this view, but it is important to recognize that the legal status of animals and the protections afforded to them in many countries largely reflect this kind of view. As for equal and unequal moral consideration views, perhaps the best way to approach their critique is to ask whether we can identify any good reasons for giving animals less moral consideration than we give to humans. If we cannot find any good reasons, then we are being arbitrary in discounting animals' interests. One possibility is that humans deserve greater moral consideration than nonhumans simply in virtue of belonging to the species Homo sapiens - but this view has been extensively criticized as being arbitrary, since species - like race or gender - does not seem to be morally relevant. A second and more plausible option is that humans deserve greater moral consideration because we are more cognitively complex - but this view may have unpalatable implications for the moral standing of non-rational humans. Finally, we may say that humans gave greater moral standing because they are part of our community. The main challenge to this view is that while community membership may impose greater obligations of assistance, it is less plausible that we are entitled to harm others outside of our community.
References
1. DeGrazia D. Animal Rights: A Very Short Introduction. New York: Oxford University Press; 2002.
2. Rachels J, Rachels S. The Elements of Moral Philosophy. 6th ed. New York: McGraw Hill Higher Education; 2010.