Do We Have an Obligation to Eat Animals? No.

If only they could talk, they would say, “thank you for discharging your duty to kill and eat us.” (By Watershed Post — Meat hanging in the first cooler room of the processing facility, CC BY 2.0,

The history of human thinking about animal ethics is littered with a great many examples of smart people engaging in reasoning that is anything but smart in order to justify continuing to exploit animals. Indeed, animal ethics provides what might be the greatest example of how self-interest — in particular gustatory self-interest — can deaden even the keenest intellectual faculties. A recent example of this tragic phenomenon is found in an Aeon essay, “Why You Should Eat Meat,” by Nick Zangwill. (The Aeon essay is a shorter version of the argument that Zangwill made in “Our Moral Duty to Eat Animals,” published in the Journal of the American Philosophical Association.) Zangwill is a respected philosopher who claims that if we care about animals, we have a moral obligation to eat them. But just as Zangwill thinks we have a duty to eat animals, I think I have a duty to point out that Zangwill’s arguments in support of animal use are just plain bad. In this essay, I will focus primarily on Zangwill’s Aeon essay.

Zangwill maintains not just that it is permissible to eat animals; he says that, if we care about animals, we are obligated to breed, raise, kill, and eat animals. His argument for this involves an appeal to history: “Breeding and eating animals is a very long-standing cultural institution that is a mutually beneficial relationship between human beings and animals.” According to Zangwill, this cultural institution has involved providing a good life to animals and food for humans, and he believes that we have an obligation to perpetuate this as a way of honoring that mutually beneficial tradition. He says that those of us who do not eat animals are acting wrongly and are letting the animals down. He says that “[v]egetarians and vegans are the natural enemies of domesticated animals that are bred to be eaten.” The idea that domesticated animals owe their existence to those who consume them is not new. Sir Leslie Stephen, English author and father of Virginia Wolff, wrote in 1896: “The pig has a stronger interest than anyone in the demand for bacon. If all the world were Jewish, there would be no pigs at all.” Stephen did not, as far as I am aware, take the additional step that Zangwill does and claim that at least non-Jews have a moral obligation to eat pigs.

Zangwill sees eating animals as a way of respecting and honoring the past. (Indeed, he uses the language of “respect” and “honor” in his Journal article.) Zangwill wants to distinguish his position from that of Peter Singer, who argues that we can justify eating at least some animals (those who are not self-aware) as long as those animals have had reasonably pleasant lives and relatively painless deaths and are replaced by animals who will also have reasonably pleasant lives. Zangwill claims that his argument is not a consequentialist argument focused on maximizing overall human and nonhuman happiness and preference satisfaction, but a deontological one: the obligation is generated by the historical tradition. The obligation is one of respect for the mutually beneficial relationship that developed historically. He maintains that the obligation to eat animals applies only to animals who have “good lives.” As to why it is not okay for us to use and kill humans, he reiterates a version of the same old framework that Singer and many others employ: humans are just special.

A great many observations could be made about Zangwill’s position. Here are three.

I. Zangwill’s Appeal to History

Why? Patriarchy benefits women. Doesn’t it? (Photo by chloe s. on Unsplash)

Zangwill maintains that we have an obligation to eat animals because that is what respect requires for the mutually beneficial institution that has provided benefits in the past, and continues to provide benefits, for humans and nonhumans. We get meat and other animal products. Animals get a good life. But the fact that we did something in the past does not mean that that is the morally right thing to do in the future. Even if animals get some benefit from the practice, they undoubtedly suffer some harm on anyone’s view, and saying that this has gone on for a long time does not mean that it should continue.

Let’s focus on a couple of similar arguments involving humans. Human slavery has existed throughout history. Indeed, it was often described as a “natural” institution because of its prevalence throughout human history, including its favorable mention in the Bible. It was common to argue that, although slave owners and others certainly benefitted from slavery, slaves received all sorts of benefits from being enslaved, and that this justified slavery. For example, it was often claimed that slaves were treated better than free people; they received care that often exceeded that which free people who were poor received. Indeed, that very argument was made in the 19th century to defend race-based slavery in the United States.

Consider also patriarchy, male domination in public and private spheres. Patriarchy is another institution thought at various times (including the present time by some) to be defensible and one that also makes favorable appearances in the Bible and other religious texts. Patriarchy has been defended on the ground that it has existed for centuries, and allegedly involves mutual benefit. Men benefit from it but women benefit from it as well. In a patriarchal society, men have all the stress and pressure of being successful and successfully being dominant; women don’t need to worry about all that and are cared for.

Most of us would reject these arguments. We would recognize that the fact that an institution (slavery, patriarchy) has existed for a long time is irrelevant to whether the institution is morally justified now even if there is some benefit that the slaves or the women receive, or even if some men or some slaveowners are/were more benign than others. Patriarchy, however benign, necessarily involves at least ignoring the interests of women in equality. Slavery, however benign, necessarily involves at least ignoring the interests of those enslaved in their liberty. Being serious about morality requires that we reassess our position on matters. We now see claims that slavery or patriarchy involve mutual benefit as ludicrous. Relationships that involve structural inequality that guarantee that at least some fundamental interests of humans will be discounted or ignored cannot, irrespective of benefit, be justified, and they do not provide the grounding for any obligation to respect and perpetuate those institutions.

The same analysis applies to our use of animals. Yes, humans (although not all humans) have been eating animals for a long time. In order to exploit animals, you have to keep them alive long enough so they get to whatever age or weight you deem optimal to kill them. In this sense, animals have benefitted from the “care” that humans have given them. But that fact, without more, cannot ground a moral obligation to continue the practice. As in the cases of slavery and patriarchy, the relationship of humans to nonhumans involves a structural inequality: animals are the property of humans; humans have property rights in domesticated animals, who are bred to be submissive and subservient to humans, and humans are allowed to value animal interests and to kill animals for human benefit. Because animals are economic commodities and it costs money to provide care for them, the level of that care has tended to be low and to not exceed, or not exceed by much, the level of care that is economically efficient (such that lesser care would be more costly). The fact that this efficiency model has reached an extreme point with the advent of the technology that made factory farming possible should not blind us to the fact that things were not all roses for animals on smaller “family farms.” The property status of animals means that, at the very least, some interests of animals in not suffering will necessarily have to be ignored; and, because our use of animals involves killing them, the interest of animals in continuing to live will necessarily have to be ignored. To call this a relationship of “mutual benefit” given the structural inequality is, as it was in the cases of slavery and patriarchy, nonsense; to maintain that this situation creates a moral obligation to perpetuate it assumes that the institution of animal use can be morally justified. As we will see below, Zangwill’s argument here is not an argument at all; Zangwill simply asserts the necessary deprivation of life entailed by institutionalized animal use isn’t a problem because animals are cognitive inferiors that don’t have an interest in continuing to live anyway.

Putting aside that the tradition of killing and eating animals was not universal — so there was a competing tradition that he ignores — Zangwill also ignores that we now have a very different food system and knowledge of nutrition than we had when the tradition of animal use for food developed. We now recognize that we no longer need to eat animal foods for nutrition. Indeed, an increasing number of mainstream health care professionals are telling us that animal foods are detrimental to human health. Zangwill explicitly recognizes that human beings can live as vegans, and have no need to consume meat or animal products. Surely, the fact that we don’t need to use animals for nutrition purposes has an effect on our moral obligations to animals, particularly given that most of us think that the imposition of “unnecessary” suffering is wrong. Zangwill does not even discuss this issue. He says that we should not kill wild animals for sport and may only kill them if we have a real need to do so: “They have their conscious lives, and who are we to take it away from them without cause?” Well, if we have no need whatsoever to kill any sentient, or subjectively aware, animals for food, including domesticated ones, and if we take suffering seriously as a moral matter and think that imposing “unnecessary” suffering is wrong, how can we justify the institution of animal use for food much less derive an obligation that we must continue to eat animals? We not need embrace animal rights to see that Zangwill’s position is wrong; we just need to accept Zangwill’s own view that the suffering of animals is morally significant. If it is, then we cannot impose suffering in the absence of need, unless, of course, Zangwill wants to take a consequentialist position and maintain that animal suffering incidental to non-necessary use is outweighed by human pleasure, which he says he does not want to do.

Zangwill would probably reply that, because we have caused domesticated animals to come into existence, we have the right to kill them. But how does that follow? We cause our children to come into existence; is it okay to use and kill our children because we have caused them to come into existence? Slave owners often forced slaves to breed; was it okay for slave owners to sell the children who were thereby caused to come into existence? The fact that X causes Y to come into existence does not mean that it is morally acceptable (much less obligatory) to inflict suffering or death on Y. Zangwill would probably say that those cases are different from the animal situation because humans are special. But that is not a satisfactory answer. I will discuss this in the third part of this essay.

II. Zangwill and the “Good Life”

Every animal we kill and eat needs one of these. Photo by dominik hofbauer on Unsplash

Zangwill maintains that his argument that we are obligated to eat animals based on his appeal to the historic tradition of mutual benefit applies only to animals who have a “good life.” The element is crucial for Zangwill because his central claim is that animal use is a benefit for the animals who are eaten.

Whether animals raised on small farms that do not practice intense confinement have “good lives” is a matter of debate; but whether animals who are raised and slaughtered in the system of mechanized death called “factory farming” have a “good life” is not up for debate. They don’t. Zangwill seems to recognize this although he hedges a bit, at least in the Aeon piece, and does not present a full-throated condemnation of all factory farming, preferring to target “the worst kind of factory farming” and “very intensive factory farming.” To the extent that Zangwill believes that any factory farming results in animals having a “good life” — to the extent that, for example, he thinks that conventional egg batteries do not result in a good life but “cage-free” barns and “enriched” cages, both of which are criticized even by conservative animal welfare charities as imposing significant suffering on animals, are okay — then his position is even more bizarre and indicative that he knows little about factory farming. In any event, I will read him as saying that his argument does not apply to any factory-farmed animals.

The problem here is that only a small amount of meat and other animal products are produced outside the factory-farm system. Estimates vary but a conservative one is that 95% of animals in the U.S. are raised on factory farms, and more than 70% of animals in the U.K. are raised on factory farms. In other words, only a small fraction of animals may be said to have a “good life” if we assume that animals used for food but not on factory farms have a “good life.” And even if the animals are raised in a supposedly “higher-welfare” situation, most of them are slaughtered in mechanized abattoirs. So, to the extent a “good life” includes not having an absolutely horrendous death, it not clear whether there is anything but a very small fraction of animals who would satisfy Zangwill’s criteria for having a “good life.”

In any event, what is the relevance of the historical tradition upon which Zangwill relies if it is providing the morally relevant level of benefits only as an exception and not as a rule? Why does the tradition matter at all when it is only observed in the breach and only when a minority of animals benefit even on Zangwill’s terms? I suppose Zangwill could say that percentages don’t matter and if only .0001% of animals were accorded a “good life” as a historical matter, that would still be a great many animals, and would serve to establish a practice that we are required to respect by continuing to eat “happy” animals. But that would make his appeal to history rather anemic because he is attempting to ground an obligation on an institution that he identifies as humans eating animals under circumstances in which animals were beneficiaries of a good life. It is not clear how he could ground this obligation on what might be only a practice that involves a relatively small number of animals. Zangwill could, of course, forget about the historical tradition argument altogether and take the position that animal use provides a benefit for the animals used as long as those animals have a “good life,” and that we ought to act to create that benefit because the world is better with it than without it. But then, his argument would be little more than a consequentialist one — that, in order to maximize happiness, we have an obligation to bring into existence and to consume animals who have had reasonably pleasant lives. This would help Zangwill avoid the irrelevance of a tradition that no longer exists (if it ever did) as well as the general problem of making an appeal to tradition. But it also would make his position pretty much identical to Singer’s.

I should add that it is curious how Zangwill picks and chooses whose culture counts. For example, he claims that the appeal to tradition would not apply to dogs because the tradition there involved producing animals for companionship or work and not for food. But there is evidence that eating dogs occurred in China, amongst the Aztecs and some North American indigenous peoples, Polynesians and Hawaiians, and others. So it would appear as though Zangwill would have to conclude that the obligation to eat dogs who have had “good lives” exists in those cultures.

III. Zangwill and the Cognitive Inferiority of Nonhuman Animals

“I am not sure why I am doing this. Therefore, you can kill and eat me.” (Photo by Vidi Drone on Unsplash)

Zangwill is aware that his analysis is open to criticism on the ground that, if you apply it to humans, you get some pretty nasty results. So what is his solution? He trots out the well-worn invocation of anthropocentrism. We can reject patriarchy and slavery, but embrace animal exploitation and, indeed, find it to be morally obligatory, for the simple reason that humans are special; they have characteristics that are special. And those humans who, for reasons of age or disability, don’t have those characteristics, are still special because they are members of a species whose normally functioning adult members have those special characteristics. In other words, as long as you’re human, whether you actually have the special characteristics or not, you are special. It never ceases to amaze me that intelligent people so often fail to see the problem with that approach.

Philosophers have, for the most part, argued that we may use and kill animals because they are not rational and self-aware, and, as a result, they live in a sort of “eternal present” and have no significant connection with a future self. If we kill them, they really have no sense of losing anything. In other words, even benign slavery is problematic because those enslaved have an interest in liberty that is necessarily ignored by the institution of slavery. But animal use involves no necessary deprivation because animals do not have an interest in continuing to live in the first place. Zangwill joins the chorus here. He actually demands more than rationality and self-awareness as those terms are used by, say, Singer, and focuses on the concept of “normative self-government,” which Zangwill describes as:

more than the ability to think about our own thoughts (often called ‘metacognition’) but […] also the ability to change one’s mind, for instance, in forming beliefs or intentions, because we think that our mindset demands it. In reasoning, of the more self-conscious kind, we apply normative concepts to ourselves and change our minds because of that.

Zangwill says that it is not clear whether apes or monkeys have this reflective reasoning but states that it is pretty clear that elephants, dogs, cows, sheep, chickens, etc. do not have it. He says that pigs may have it so, with respect to animals other than pigs, “we do not have to wait and see what the research turns up; we may proceed directly to the dinner table.” He ends his Aeon essay with this statement: “We can ask: ‘Why did the chicken cross the road?’ but the chicken cannot ask itself: ‘Why should I cross the road?’ We can. That’s why we can eat it.”

Putting aside Zangwill’s attempts to be iconoclastic, why is “normative self-government” — or any humanlike cognitive characteristic beyond sentience — necessary to have a morally significant interest in continuing to live? Why is it important that the chicken be able not only to be subjectively aware, and able to form intentions to engage in actions, but to be able to “apply normative concepts” and change her/his mind as a result of the application of those normative concepts, in order to have a morally significant interest in her/his life? Zangwill never explains that because he can’t. That’s the advantage and disadvantage of an assertion of anthropocentrism to justify animal exploitation. You get to declare that humans are special but that’s all you do — declare it. There is no rational reason why only those who have certain humanlike cognitive characteristics (or those who, for reasons of age or disability, don’t have those characteristics but are human) have a morally significant interest in continuing to live.

I remember once, many years ago, debating a scientist who used animals in experiments. She argued that humans were special because they could write symphonies and animals could not. I informed her that I had not written any symphonies and she confirmed she had not either. But, she said, she and I were still members of a species some of whose members could write symphonies. I asked her why writing symphonies, or being a member of a species some (a very few) of whose members could write a symphony, made one more morally valuable than a being who can, say, travel by echolocation, or breathe under water without an air tank, or fly with wings, or find a location based on a bush urinated on weeks ago. She had no answer. That is because there is no answer. There is only a self-interested proclamation of superiority. The fact that Zangwill just waves the flag of anthropocentrism once again is compelling evidence that those who want to continue to exploit animals don’t have a great deal to say. The invocation of anthropocentrism is as vacuous as arguing that we should continue to eat animals because Hitler was a vegetarian or because plants are sentient.

In my book Why Veganism Matters: The Moral Value of Animals, I discuss the idea, accepted by many philosophers, that sentience, or subjective awareness, alone is not sufficient to give rise to an interest in continuing to live. I argue that sentience is a means to the end of continued existence and to talk about sentient beings as not having an interest in continuing to live is like talking about beings with eyes who lack an interest in seeing. I argue that all sentient beings have a morally significant interest in their lives, and that we cannot use and kill them, particularly in situations in which there is no necessity to do so.

Although I do not think that animals, or at least most of those we routinely exploit for food, live in an eternal present, we do not doubt that humans who do live in an eternal present have a morally significant interest in their lives. That is, as long as humans are subjectively aware, we regard them as persons. For example, there are some humans who have late-stage dementia. They are certainly as stuck in an eternal present as is any nonhuman. But we regard these humans as being self-aware if only in the present and as having a connection with a future self if only that self in the next second of consciousness. They value their lives on a second-to-second basis. This is not a matter of thinking that these humans are persons just because they are members of the human species, as Zangwill would have it. On the contrary; we recognize these humans as persons in their own right. We understand that any attempt to posit criteria other than subjective awareness to ascertain the “right” level of self-awareness or connection with a future self is fraught with the danger of compete arbitrariness.

For example, is there a morally relevant difference between X, who has no memory and no ability to plan for the future beyond the next second of his consciousness, and Y, who has late-stage dementia but who is able to remember one minute in the past and plan for one minute into the future? Is Y a person and X not a person? If the answer is that X is not a person but Y is, then personhood apparently comes into being somewhere in the fifty-nine seconds between X’s one second and Y’s one minute. And when is that? After two seconds? Ten seconds? Forty-three seconds? If the answer is that neither are persons and that the connection with a future self requires a greater connection than one minute, then when, exactly, is the connection with a future self sufficient for personhood? Three hours? Twelve hours? One day? Three days?

The idea that we apply a different framework where nonhuman animals are concerned, and actually demand that animals be capable of “normative self-government” in order to have a morally significant interest in continuing to live, is just a matter of anthropocentric prejudice and nothing more.


As I stated at the outset, Zangwill provides an excellent example of a philosopher whose desire to eat animals has very profoundly clouded his thinking. Zangwill appeals to a tradition that no longer exists — if it ever did — and makes no argument other than the assertion of anthropocentrism to justify the tradition in the first place. But I understand the appeal of these sorts of essays. Zangwill is telling some people what they want to hear. The philosophical literature is replete with efforts to justify animal exploitation that are all more or less based on the assertion that we can continue to use animals because they are inferiors and we are special. But Zangwill goes beyond even that; he not only gives us a reason to justify our continuing to eat animals; he tells us that, if we care about animals, we must continue to do so. Talk about reassuring! Never mind that the reason that eating animals is okay and obligatory is that chickens are, for instance, unable to plan sabbaticals. If you want to do something badly enough, any reason is as good as any other.