Philosophy > General AR Philosophy

The Failure of the Kantian Theory of Indirect Duties to Animals

Heather Fieldhouse, PhD

Kant famously holds that we have no direct duties to animals, but we have indirect duties with regard to them.  One of his key points in this argument is that we ought not treat animals cruelly, as it damages our natural sympathies and thus can harden us in our dealings with other human beings.  Thus our duties with regard to animals are actually duties to human beings.  We use them as means to our ends, or even kill them, but we must avoid being cruel as we do it (6:443, 27:458-460). 

These conclusions are reminiscent of what is sometimes termed an animal welfarist position, in that animals have no rights, but we still ought not to treat them cruelly and must strive to minimize their suffering.  However, it is important to note that whereas an animal welfarist typically holds that the source of these duties (however minimal) is some morally relevant feature of the animal itself, Kant holds that our obligation to avoid mistreating animals is not really an obligation to the animals themselves.  Instead, it is an obligation to ourselves and to other human beings, the fulfillment of which in some cases happens to involve the treatment of animals.  The animals themselves are mere things without moral worth. 

Such views are today widely considered to be antiquated, prejudiced, and anathema to champions of animal rights and liberation. As Kant’s theories and ethical tradition is still very influential in the contemporary arena, however, Kant cannot be easily dismissed. Kantian ethics is at its best when it deals with humans, using powerful concepts of respect, and dignity,  and inalienable worth, such as are related to current notions of rights.  Kant provides an appealing alternative to utilitarianism for those who hold fast to the belief that some actions are wrong regardless of the possible benefit derived from them.  Utilitarianism, after all, affords no rights or fundamental protections to anyone, except the right to have one’s interests given equal consideration in the grand calculation.  Although utilitarianism was a huge advance in that it made sentience not reason the basis of moral consideration, and thereby brought animals into the scope of ethical consideration, it leaves the door open for those who would claim that at least some cruel uses of animals can be justified by the greater happiness that would result for human beings. 

As argued by animal rights theorists, indirect duties is grossly inadequate for the purposes of protecting animals from unjust exploitation. But in order to provide for direct duties to animals, a Kantian would have to substantially revise Kant’s claims about the source of moral value.  Moral considerability and moral agency are closely linked in the Kantian framework; separating them would not be a trivial task. In this essay, I will argue that the attempt by Kant and his followers to establish indirect duties to animals as an adequate moral framework regarding animals is unsuccessful.  Kant’s defenders have been unable to rectify its two primary flaws: that it is deeply counterintuitive, and that it rests on a dubious psychological claim.  As a result of these failings, Kantianism cannot provide a firm basis for even minimal duties to animals.

Kant’s Contemporary Defenders

The basic implausibility of Kant’s indirect duty theory has led some Kantians (Christine Korsgaard and Allen Wood being two recent examples) to discard it in favor of a Kantian approach that acknowledges direct duties to animals.  Their task is difficult.  Kant makes moral agency, which he equates with rational autonomy, the source of all moral worth.  Even if we recognize (as Kant did not) that many animals have some ability to use reason to solve problems, it would not be enough to show that they have moral value for Kant, since the type of rationality that he is concerned with is moral reasoning – the ability to set ends for oneself according to the dictates of morality.  In order to provide for direct duties to animals, a Kantian would have to substantially revise Kant’s claims about the source of moral value.  As moral considerability and moral agency are closely linked in the Kantian framework, separating them is a difficult task.

Faced with such a daunting alternative, some recent Kantians have tried to defend Kant’s indirect duty view against claims of implausibility, and to show that Kant’s view allows for a satisfactory level of obligation with regard to animals.  Dan Egonsson, for instance, tries to show that it can go beyond just the basic prohibition against wanton cruelty, and be used to defend ethical vegetarianism.

According to Kant, being cruel to animals tends to make a person also insensitive to his fellow man; that is why apparent duties to animals are actually indirect duties, since ultimately they are duties to mankind.  This argument does not seem to apply to meat-eating, however, since it is possible to eat meat without being involved oneself in the raising and slaughtering of the animal; in fact, most people are very distanced from this process.  Egonsson, however, writes that we can plausibly extend Kant’s remarks to also encompass accepting cruelty to animals (477).  Anyone who eats intensively-farmed meat is implicitly accepting cruelty to animals.1 Accepting cruelty to animals means accepting that other people are being desensitized to suffering in the way that Kant describes.  This could result in their humanity being damaged, and could lead to their treating other human beings with cruelty as a result.  He concludes that a Kantian should therefore regard vegetarianism as a duty. 

Egonsson shows that an indirect duty theory would not necessarily be limited to a very narrow obligation to avoid wanton cruelty.  In addition to endorsing vegetarianism, such a theory could similarly show that many of our current uses of animals are wrong.  The endorsement of the indirect duty view could have some rhetorical value for animal protection groups, since it would link the treatment of animals with duties to humans, thus sidestepping the more controversial and less generally-accepted claim that animals have intrinsic rights.

Although the indirect duty view has some benefits, I believe that its flaws cannot be overlooked. Attempts to reconcile the indirect duty view with contemporary sensitivity about animal issues have failed to rescue it from its two central problems.

The Problem of Counterintuitive Implications

The first of the two main problems with the indirect duty view is that it has certain consequences that are extremely counter-intuitive.  If torturing animals had no effect on our attitude towards other humans, then according to the indirect-duty view, we would have no obligation to refrain from doing it.  Most people would want to say that it would be wrong even if  it had no effect on our treatment of human beings, but indirect-duty theorists must reject this claim.  Furthermore, as noted by Wood, if it happened that somehow torturing animals made us kinder to humans (for instance, by allowing us to release aggression), then we would be obliged to do it (194-195).

Christina Hoff gives the example of a man who has always acted kindly towards his family and towards human beings in general, but who is in the habit of secretly burning stray dogs to death.  According to Kant, he would not be wronging the dogs, since we have no duties to dogs.  Instead, he would be guilty of wronging humanity, because such dealings with animals tend to make one hard towards human beings.  The terrible suffering of the dogs is in itself of no importance.  Indeed, before the arrival of mankind on the evolutionary scene, no animal suffering or happiness had any value whatsoever; and upon the awakening of rationality, it took on a merely indirect significance.  Hoff regards this as implausible and counter to our moral intuitions (67).

In Hoff’s view, this implausible claim belies a deep flaw in Kantian ethics.  “If there are any moral truths,” she writes, “this one is clearly among them: suffering is an evil, and gratuitously and deliberately to inflict pain and suffering is a moral evil.  This needs qualification, but we must be wary of any moral theory . . . that loses sight of it” (68).  Furthermore, Kant is unable to satisfactorily account for mentally impaired humans in his ethics: either they are simply means to an end, like animals, or else some sort of leeway must be introduced to allow them moral recognition – but any such leeway is likely to make it even more difficult to exclude animals.  “It is implausible that our duty to feed a hungry retarded child would turn out to be indirect and, in this respect, essentially distinct from our duty to feed a normal child” (68).

Are the counterintuitive consequences of Kant’s view a problem, aside from making the position unpalatable?  Alexander Broadie and Elizabeth Pybus point out that, since Kant believed his moral system to accord with the ordinary moral intuitions of the common person, it is legitimate to criticize his framework if it does not in fact accord with these intuitions.  Arguing from intuition is always fraught with peril, however, since intuitions are seldom universal.  Furthermore, it is probably impossible for any consistent theory to satisfy all our intuitions.  There is, however, another strong criticism of Kant’s theory which does not rest on intuitions.

The Problem with Establishing the Causal Connection

The second main problem cited against Kant’s theory is that he cannot successfully make the causal connection between cruel treatment of humans and cruel treatment of animals.  Broadie and Pybus show that Kant believes this connection is founded on an analogy.  Although animals are only things and not persons, Kant claimed that they have some qualities which are analogous to human qualities (377).  However, “His claim that animals are analogous to persons appears to mean no more than that they behave as if they have psychological states that we take to characterize people” (378).  There is no further claim being made; Kant certainly does not mean that they have anything like a faculty of reason.

Although according to Kant animals are things with features analogous to ours, they are nevertheless still things, and therefore we do not have direct duties to them.  Kant refers to the mistaken notion that we have duties to beings other than men as an amphiboly of the moral concepts of reflection (6:442).  Broadie and Pybus note that Kant uses the term “amphiboly” to refer to a mistake in reasoning (379).  In the context of ethics, Kant defines amphiboly simply as “taking what is a human being’s duty to himself for a duty to other beings” (6:442).  This means that our feeling of obligation towards animals is based on a misunderstanding.

Although Kant argues that we do not have direct duties to animals, “he holds that maltreatment of animals is wrong first because it leads us to be unsympathetic to . . . other people.  In other words it leads us to treat other people merely as a means” (Broadie and Pybus 382).  Second, it is wrong because it does violence to our own humanity, i.e., it leads us to treat ourselves as a means.  

Broadie and Pybus regard this position as inconsistent, because Kant is claiming that in using certain things (animals) as means, by analogy we are led to treat people as means.  Kant cannot point to any morally relevant difference between an animal and any other sort of mere thing, since the only possible morally relevant difference would be the possession of rationality, which animals do not have.  Therefore, the authors claim, Kant is forced to say that nothing may be used as a means;  we have an indirect duty to any thing not to use it as a means.  “This is not merely absurd, but contrary to his imperative of skill” (382).  They also claim that Kant cannot prove even an indirect duty to animals, because Kant’s position rests on a speculative psychological claim about human nature – that cruel dealings with animals make people hard towards other people – which, even if he could prove it true, is irrelevant because it is “a contingent matter of fact about human beings, and not a fact about rational beings” (382).

That it is a matter of fact about human beings and not about all rational beings should not be a problem for Kant.  It is true that Kant regards the moral law as applying equally to all rational beings (including nonhuman rational beings, if they prove to exist), but contingent, empirical facts can affect how the moral law is expressed.  For instance, lying is morally wrong according to the moral law, but in order for there even to be such thing as lying, we have to be the sort of beings who can communicate with each other, and who can express themselves falsely, and so on.  The specific fact in this case involves the psychology of human beings, but the maxim (i.e. the rule according to which one acts) could be construed as “I will not perform actions that tend to harm my ability to behave morally.”  This rule would apply to any rational beings, but in order to it, we do of course have to look at the empirical facts about what does tend to harm this ability in a certain type of being.

Tom Regan responds to the aforementioned article with the remark that, although Kant’s position may go against intuition, it is not internally inconsistent.  Kant never claims, Regan points out, that we ought not use animals as means (as beasts of burden, for example).  He claims that we ought not maltreat them, which is a narrower claim.  “For we can, given Kant’s views, use an animal as a means without at the same time necessarily maltreating it, as when, for example, a blind man uses a seeing eye dog but treats him with love and devotion” (471).

Regan’s response is brief, and does not address the central problem: what does it mean to maltreat something?  We cannot define it as “to use something in such a way that goes against rationality (or morality)” because that begs the question.  Maltreating something cannot merely mean using it as a means, for the reasons that Regan gives. 

There is a hint in the Lectures on Ethics where Kant is reported as saying, “Vivisectionists, who use living animals for their experiments, certainly act cruelly, although their aim is praiseworthy, and they can justify their cruelty, since animals must be regarded as man’s instruments; but any such cruelty for sport cannot be justified” (27:460). So, maltreating an animal for Kant is treating it with unnecessary cruelty.  Whether a given cruelty is necessary is probably dependent on whether it is required for fulfilling a direct duty (or possibly even an indirect duty) to human beings.

Broadie and Pybus’s analysis of the belief that we have direct duties to animals as an amphiboly, or mistaken analogy, raises an interesting point.  If it is a mistake that leads us to connect human and animal suffering, and if it is this psychological connection that leads to the causal connection between the two kinds of cruelty, wouldn’t the solution be to train ourselves not to make that mistake?  Kant’s theory seems to be aimed at damage control, rather than prevention.  Rather than accept that we will make that mistake, and then try to make sure it doesn’t harm our sensibilities, it seems better to learn not to make the mistake at all.

Skidmore makes a similar point.  A weak or moderate connection between cruelty to animals and inappropriate attitudes or behavior towards humans (i.e., that the former occasionally or usually leads to the latter) is not enough to establish indirect duties to animals.  If the weak or moderate connection were established, it would not show that all agents have such duties; only certain agents would be so obliged, and the others could treat animals however they pleased.  In order for the indirect duties to be universally applicable, it must be true that cruel treatment of animals almost always, for almost all agents, results in inappropriate attitudes or behavior towards humans (Skidmore).  There is a lack of empirical evidence for this connection, and some evidence that suggests it is false.  Surely some cultures have existed in which animals were treated brutally, without everyone in turn being brutal to each other.  Consider Spain, for instance; blood sports such as bullfighting are traditional and popular, yet there is no evidence that the people of that country are any more brutal to each other than in countries where such events are frowned upon.

The strong connection required for the indirect duty view may not be true; but even if it is true, Skidmore argues, the connection would not be a necessary one.  If, as the indirect duty theorist claims, there is a clear moral difference between humans and animals, then it should be possible for us to harm animals without harming our sympathy for fellow human beings.  In fact, since sympathy for animals sometimes can distract our attention from our true duties, it is not morally ideal.  Therefore, we ought to try to shape our sympathy “to reflect better the clear and crucial moral distinction (on Kant’s view) between animals and persons” (Skidmore).

The indirect duty theorist must then claim that shaping our natural sympathy in this way is impossible.  This claim is very implausible, given the variation among people and cultures.  Skidmore uses the example of abortion.  Some people have an acute sympathy even for embryos, whereas others see them as nothing more than inconsequential tissue. “It seems rather obvious that many people can and do shape their sympathies to reflect more adequately the moral beliefs they come to hold” (Skidmore).

An additional point along these lines (though not raised by Skidmore) is that at least some agents will, in the course of fulfilling their duties to humans, have to inflict acute suffering on animals.  The researcher who must injure, poison, and inflict diseases upon animals for the benefit of humankind knows that this is his duty.  It seems that he has two choices: he can unlearn his natural sympathy for animals because of his understanding that it is not morally appropriate; or he can harm animals despite his sympathy, and therefore also damage his sympathy for human beings.  The latter would be immoral for the indirect duty theorist, but if the former is possible then the strong connection does not hold.  Either the indirect duty theory must be abandoned, or else it must become so strong that any use of animals which causes suffering – including medical research –  is forbidden.  That may sound like an inviting approach, but it would no longer be plausible to regard it as an indirect duty view at that point.  The idea behind indirect duties is that our improved treatment of animals is really aimed at fulfilling our obligations to humans; humans are still the center of the moral universe.  Yet surely if that were true, we would be justified in harming animals in at least those few cases (probably fewer than most people, Kant among them, recognize) where it would be required to directly support human interests.  Furthermore, as previously noted, the strong connection that would be required for such a view (that harming animals results in mistreatment of humans almost always) is not plausible.

A Different Version of the Indirect Duty View

Peter Carruthers has defended an indirect duty approach to animals, but with a shift in emphasis that allows him to avoid some of these difficulties.  Whereas Kant claims that cruelty to animals tends to cause people to become hard in their dealings with other human beings, Carruthers claims that cruelty to animals reveals an existing flaw in the agent: a general indifference to suffering, which will probably also express itself in the agent’s dealings with human beings (153-154). 

One advantage to Carruthers’s approach is its empirical plausibility.  Animal welfare organizations often emphasize a link between violence against animals (especially in youth) and violence against humans.  The implication is often that the former causes the latter; much has been made of the fact that many infamous murderers were previously caught abusing animals.  It could just as easily be said, however, that some underlying character flaw (indifference to, or even enjoyment of, others’ suffering) is responsible for both the animal and the human cruelty.  Carruthers is therefore not faced with the difficulty of showing how the one type of cruelty causes the other; he only needs to show that there is a connection.  Furthermore, his view better accounts for the case of the vivisectionist.  The person who torments a dog for no good reason reveals something different about her character than does the person who reluctantly torments a dog because she believes it will save human lives.

The problem with Carruthers’s view is that although it may show why we have a repugnance towards animal cruelty, it does not show that these actions are immoral.  If, as Kant holds, being cruel to animals causes us to be cruel to humans, then we have a duty to refrain from being cruel to animals.  If the animal cruelty is only a symptom of a character flaw, rather than the cause of it, then it would be deplorable but not evil.  We would have no duty to refrain from it, though we would be justified in passing unfavorable judgment upon the moral character of those who engaged in it.  Carruthers gives the example of Astrid, an astronaut who has brought her cat into space with her on a one-way trip out of the solar system (thus ensuring that no other human beings will be distressed in any way by her actions).  At some point in the journal, Astrid gets bored, and decides to entertain herself by hanging her cat from the wall and using it as a dartboard.  According to Carruthers, “Such actions are wrong because they are cruel.  They betray an indifference to suffering that may manifest itself . . . in that person’s dealings with other rational agents” (153-154).  He concludes that “actions which cause suffering to animals will be wrong whenever they are performed for no reason, or for trivial reasons” (154). 

Carruthers has not, however, established that Astrid’s action was wrong, only that she is an unpleasant person, and is likely to commit moral wrongs in the future.  Her actions reveal something about her character, to be sure, but this does not prove that the actions themselves are wrong.  By way of analogy, consider the mother who suspects that her son’s style of dress indicates that he is involved with the drug culture.  This seems to be good reason for her to be concerned about his character and lifestyle, and perhaps even to find his style of dress unpleasant.   However, it does not mean that his clothes are inherently harmful, and if she responds by forbidding him to wear them, most would think her prohibition is misguided.  If the clothes caused the lifestyle, then the prohibition would make sense.  Hence an indirect duty view, to successfully establish that we ought to refrain from being cruel to animals, must establish that such cruelty itself causes the character flaw that leads to cruel treatment of humans, as Kant maintains.

Since the causal approach is just as problematic as Carruthers’ revealed-character approach, I believe that the attempt to establish indirect duties to animals is unsuccessful.  I conclude that a Kantian has two options: either accept the counterintuitive result that we have no duties at all (indirect or direct) to animals, or try to find some other way to establish duties to animals within Kant’s system.  Since the connection between rationality and moral considerability is deeply rooted in Kant’s ethical theory, this is no small task.  Given the enduring influence of Kantian ethics, however, it would be a worthwhile endeavor.

Heather Fieldhouse completed her Ph.D. in Philosophy at Michigan State in May 2004. She is currently a visiting assistant professor in the Center for Integrative Study in the Arts and Humanities at Michigan State University.


1. Egonsson uses the example of intensively-farmed meat presumably because humanely-raised animals that are killed painlessly would not be suffering; since animals are only means, there would be nothing wrong with killing them for food provided there is no cruelty involved with the raising and slaughtering.  Nevertheless, since most of the meat which is readily available probably does not meet this ideal standard, Egonsson’s extension of Kant’s position would tend to lead to vegetarianism.


Broadie, Alexander and Elizabeth M. Pybus.  "Kant's Treatment of Animals."  Philosophy 49. 1974: 375-383.

Carruthers, Peter.  The Animals Issue.  Cambridge: Cambridge UP. 1992.

Egonsson, Dan.  "Kant's Vegetarianism."  Journal of Value Inquiry 31.4. 1997: 473-83.

Hoff, Christina.  "Kant's Invidious Humanism."  Environmental Ethics 5. 1983: 63-70.

Kant, Immanuel.  Metaphysics of Morals. Trans. and ed. Mary J. Gregor.  Cambridge: Cambridge UP, 1996.

Kant, Immanuel. Practical Philosophy.  Trans. and ed. Mary J. Gregor.  Cambridge: Cambridge UP. 1996.

Kant, Immanuel. Lectures on Ethics.  Trans. Peter Heath.  Ed. Peter Heath and J. B. Schneewind.  Cambridge: Cambridge UP. 1997.

Korsgaard, Christine.  "Fellow Creatures: Kantian Ethics and Our Duties to Animals."  Author's personal web site.  Harvard University.  April 12, 2004. 

Regan, Tom.  "Broadie and Pybus on Kant."  Philosophy 51. 1976: 471-72.

Skidmore, James.  "The Incoherence of Indirect Duties Regarding Animals." Central Division Meeting.  The American Philosophical Association. Hyatt Regency, Minneapolis.  2-5 May 2-5, 2001.

Wood, Allen.  "Kant on Duties Regarding Nonrational Nature I."  Proceedings of the Aristotelian Society Supplement 72. 1998: 189-210.


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