Given the popularity of these viral images and the influence this thinking has on certain sections of the Left, it’s worth taking a closer look at the idea of speciesism.

Gay was subsequently inundated with hundreds of messages from incensed animal-rights activists, who insisted that “animal lives matter” and accused her of speciesism. The next day, the hashtag #AllLionsMatter was trending on Twitter.

The recent illegal killing of Cecil the Lion has also brought this dynamic to light. Author Roxane Gay tweeted her thoughts on the hypocrisy of white Americans who were outraged about the lion but expressed no concern for ongoing police murders of African Americans, writing : “I’m personally going to start wearing a lion costume when I leave my house so that if I get shot, people will care.”

Those who count animal-rights activists or vegan evangelists among their Facebook friends will no doubt be familiar with this sort of framing: it often involves inflammatory memes juxtaposing images of factory-farmed chickens with images of slave ships or Nazi concentration camps. Israeli animal-rights activists also drew this parallel in a recent viral video , explicitly describing a truck full of chickens as “just like what my grandparents experienced during the Holocaust.”

People influenced by Singer’s concept of speciesism often use it in a stronger sense — and deploy it less carefully than Singer himself does. The concept of speciesism is a cornerstone of the animal-rights movement, whose members tend to categorize it alongside (if not ahead of) forms of human oppression such as racism and sexism.

given that some human beings — most obviously, those with profound intellectual impairment — lack this capacity, or have it to a lower degree than some nonhuman animals, it would be speciesist to claim that it is always more seriously wrong to kill a member of the species Homo sapiens than it is to kill a nonhuman animal.

It is, however, speciesist to argue that monkeys should be used in medical experiments that are not absolutely necessary, simply because they are not human. He grants that killing “a being with the ability to think of itself as existing over time, and therefore to plan its life, and to work for future achievements” is more wrong than killing a nonhuman animal, but he argues that

To support this distinction, Singer focuses on the specificities of particular situations. It is not speciesist, for example, to declare that monkeys should not teach physics, because monkeys lack the ability to do so.

Singer does not think it is speciesist to think human life is more important than that of nonhuman animals in some instances. It is only speciesist to say human life is always more important.

Speciesism, as Singer defines it, is “an attitude of bias against a being because of the species to which it “belongs” — in short, discrimination against nonhuman animals. “Humans show speciesism,” he explains, “when they give less weight to the interests of nonhuman animals than they give to the similar interests of human beings.”

On May 27, 2015, as the US Supreme Court deliberated about the marriage rights of same-sex couples and the legacy of the Voting Rights Act, a New York Times interview with utilitarian bioethicist Peter Singer, famous for his philosophical work on animal liberation, asked us to consider another kind of bias: speciesism.

Singer’s New York Times interviewer is philosopher George Yancy, known for his work on race and critical whiteness studies. In the interview Yancy focuses primarily on the relationship between speciesism and racism. Singer’s answers bring up some troubling ideas.

Singer points to the indisputably horrendous treatment of animals in the industrial production of meat. As people like Eric Schlosser have shown, cows, chickens, and other animals are housed in unsanitary conditions so crowded that they are often unable to move more than a few inches. They are fed, often force-fed, a diet meant to maximize the speed of growth with no regard for their health or comfort.

In addition to food, antibiotics and steroids are used to prevent infections and stimulate even faster growth. The breeding and milking conditions of factory-farmed animals are the stuff of nightmares, as are slaughterhouses themselves.

But Singer goes much further than decrying factory farming when he equates these conditions to the conditions of slavery, specifically the system of race-based chattel slavery that Europeans and their descendants perpetrated in the Americas for more than 400 years. Yancy challenges this comparison, noting that, while it’s worth discussing the concept of equality for animals, we are still a long way from achieving it for human beings, including “black people, the disabled, women and others, here in the United States and around the world.”

Singer responds first by minimizing this failure, noting that today “there is at least widespread acceptance that such discrimination is wrong, and there are laws that seek to prevent it.” He goes on to argue:

If we were to compare attitudes about speciesism today with past racist attitudes, we would have to say that we are back in the days in which the slave trade was still legal, although under challenge by some enlightened voices.

Humans, Singer tells us, have hierarchical tendencies; we “like to think that there is always someone below us” and crave power over others. Racism, sexism, homophobia, and other forms of oppression are primarily motivated by individual “negative emotional impulses,” which may or may not be innate but are certainly mediated by culture and flow from this tendency toward hierarchy. Humans can overcome these oppressive tendencies, but consciousness must change through the intervention of “enlightened voices.”

Singer thinks human consciousness has advanced with regard to racism, contending that, while racism still exists, it is widely condemned, and that where it does persist it can be explained by people’s individual attitudes. After significant prodding by Yancy, Singer concedes that such attitudes are often reinforced by some institutions in society, but is unwilling to specify which ones. Instead he conjectures that “it would take detailed evidence and analysis to demonstrate that each of these sectors, and each of its divisions and subdivisions, involves or expresses racist practices.”

Here he apparently ignores the fact that entire academic disciplines have been doing just such work for years and have, as Yancy points out, come up with quite a bit of data regarding structural inequality and racism. Indeed, the very idea of structural racism as part and parcel of capitalism seems lost on Singer. He seems to think that, although the process is slow, racism is generally not accepted and is therefore on its way out. Speciesism, on the other hand, is more ingrained — and therefore more insidious.

Singer’s paradigm also specifies that humans and nonhuman animals should be equal where they have “similar interests.” But are human and nonhuman animals’ interests similar?

The biologist and radical Steven Rose, in his essay “Proud to Be a Speciesist,” says that the term speciesism

was coined to make the claim that the issue of animal rights is on a par with the struggles for women’s rights, or Black people’s rights, or civil rights. But these human struggles are those in which the oppressed themselves rise up to demand justice and equality, to insist that they are not the objects but the subjects of history.

Rose here is using the term in a different sense than Singer does, but his point stands. Animals, no matter what Singer and other animal rights activists may want to claim, are objects of history. To compare them with humans who have suffered and do suffer oppression — and, importantly, consciously resist that oppression — is factually wrong, not to mention reactionary.

Memes — and serious political arguments — that compare factory farms to slavery and genocide are profoundly racist. The animal-rights group People for the Ethical Treatment of Animals (PETA) is notorious for employing lynching and Holocaust imagery; in 2009, PETA members dressed in Ku Klux Klan robes outside Madison Square Garden to protest the “eugenic” breeding practices promoted by the Westminster Dog Show. Animal-rights activists also routinely appropriate the vocabulary of the nineteenth-century antislavery movement, referring to themselves, for example, as “abolitionists.”

Racism in the United States has always included comparisons of black people and other oppressed racial groups with animals, and such racist imagery is still prevalent. News stories about Black Lives Matter protests routinely include quotes from white racists accusing black activists of “rioting like animals.” The comparison is calculated to degrade, and it stems from the period when US laws treated enslaved black people as legally equivalent to livestock — categorizing them as subhuman.

Singer turns this historical fact on its head:

If we think that simply being a member of the species homo sapiens justifies us in giving more weight to the interests of members of our own species than we give to members of other species, what are we to say to the racists or sexists who make the same claim on behalf of their race or sex?

This question is tied up with the general question of whether animals have rights similar, or equal, to humans. For Singer, there is a universal moral right that applies to all living beings. He borrows this wholesale from the philosopher Jeremy Bentham’s 1789 Introduction to the Principles of Morals and Legislation . For Singer, what gives living things rights — and imposes on human beings a moral obligation to honor those rights — is their ability to suffer.

There is one point on which we do agree with Singer. He says that “Western thinking emphasizes the gulf between humans and nature,” our disconnection and alienation from the natural world — a gulf that is created by capitalism, though Singer doesn’t acknowledge this. As John Bellamy Foster, Richard York, and Brett Clark describe it in The Ecological Rift , this “potentially fatal ecological rift has arisen between human beings and the earth, emanating from the conflicts and contradictions of the modern capitalist society.”

For Singer, this gulf should give us more sympathy for the suffering of nonhuman animals. He states in the interview that that “the thinking that is characteristic of indigenous peoples” involves less of this separation. This sweeping generalization of hundreds of cultures is a problem in its own right, but let’s look at Singer’s argument on its face for a moment. Even if we grant that many indigenous peoples were or are more integrated with nature — and there is a lot of racist idealization of this relationship — it does not follow that animals should not be eaten or given equal rights to humans.

After all, we must not idealize “nature.” The food chain is a violent place; nature is, as Alfred Lord Tennyson put it, “red in tooth and claw.” It is not a Disney forest full of cute critters who all get along. There is no moral way for a cat to kill and eat a mouse. Overcoming the metabolic rift — the alienation of human beings from nature and from ourselves — would require, in part, that human beings gain a greater understanding of our place in the natural world. This includes the food chain.

Humans can do better, certainly; we can and should reduce the suffering that is endemic in our food production system. This will benefit both humans and animals. Our current factory-farming system produces low-quality food, while we could be producing much more palatable things at the same volume. It breeds disease and resistance to antibiotics. It’s also a massive source of carbon dioxide and one of the top contributors to climate change.

There is no question that a rational socialist system would make drastic changes to our current methods of food production; we might indeed eat much less meat than we do now, even if it was of a higher quality. But humanely raised and slaughtered animals could certainly be one component of a food production system created to mitigate the current rate of climate change and to feed not the hunger of profiteers but the hunger of ordinary people.

We should certainly try to alleviate unnecessary suffering when dealing with animals, but as journalist Arun Gupta pointed out in a recent speech, this is at best a case of negative rights: for example, the right of “not needlessly being subjected to cruelty.” Rights, from a materialist perspective, are meaningless outside of human existence; suffering does not necessarily confer rights. It’s only possible to talk about human rights, civil rights, or women’s rights because different groups of humans who face oppression have struggled and continue to struggle to win these rights. This is not the case with animal rights.

No animals have ever struggled to gain better treatment in food production or to oppose unnecessary experimentation by cosmetic companies. Insofar as animal rights exist, it is humans who have granted and fought for these rights. Animals themselves cannot be said to have inherent rights that we do not give them.

This discussion of rights is central to Singer’s argument that it is speciesism to claim that all human life is more valuable than all nonhuman animal life. In his 1979 book Practical Ethics , Singer flirts with eugenics by dismissing the “slippery slope” argument and arguing that “denying rights to social misfits” is unlikely to lead to totalitarianism. He insists that his aim is not to “lower the status of any humans” but to raise the status of animals. Using offensive terminology that was common at the time, he argues:

Once we allow that a grossly retarded human being has no higher moral status than an animal we have begun our descent down a slope, the next level of which is denying rights to social misfits, and the bottom of which is a totalitarian government disposing of anyone it does not like by classifying them as mentally defective.

Singer dismisses this scenario as “no more than a possibility,” though one might be forgiven for wondering whether Nazi Germany has slipped his mind. His critics contend that Singer has already traveled too far down the slippery slope, pointing to his open advocacy of infanticide for babies with disabilities. If such children are no more cognitively advanced than monkeys or pigs, Singer argues in Unsanctifying Human Life , then the only reason killing them is immoral is their membership in our species: they are valuable because they are human.

Singer argues that this tendency to assign innate value on the basis of species membership is in principle no different than a racist’s argument for superiority on the basis of racial membership and therefore cannot be defended.

Singer’s position has attracted a great deal of media attention and condemnation. In June 2015 the disability-rights groups Not Dead Yet and the Alliance Center for Independence held a demonstration on the Princeton University campus to call for Singer’s dismissal.

Tellingly, Singer’s colleague Robert George, a professor of jurisprudence, defends Singer’s academic freedom on the basis of the civility of his tone in making such arguments: “He is not a demagogue, a shouter, a hater. He sets forth his positions with clarity and defends them with rational arguments.” This defense extends no such courtesy or freedom to the many professors of color recently dismissed for criticizing Israeli policies in less measured tones; the content of the argument becomes less important than the tone in which it is expressed.

The absurdity of arguing that speciesism and racism are equivalent is quickly evident. Though science-fiction worlds like Star Trek use a variety of morally equivalent, sentient fictional species to draw analogies about racism and difference, here on Earth race is — at its core — a social construction enforced by social codes, not a biological category.

Attempts to structure ideas of race in terms of biological difference have always been deeply rooted in the material need to justify racism in order to perpetuate systems such as slavery. (See, for example, Steven Jay Gould’s classic The Mismeasure of Man for a comprehensive look at the roots of “race science” or “bioracism,” and Karen Fields and Barbara Fields’s masterful Racecraft for more on the relationship between slavery, racism, and the construction of race.)

Human beings, whatever their racial identity, possess agency. Enslaved human beings, even in the most brutal days of the chattel system, were self-directed beings who not only felt pain and experienced self-perception but who loved, reasoned, wrote, and above all fought for their own freedom. Other species will never display that kind of agency.

Ultimately, it is Singer’s individualism — his insistence on seeing racism as an individual moral and intellectual failing rather than as a social system in an unequal society — that prevents him from understanding the problem with posing speciesism and racism as equivalent. Singer argues that “we should treat beings as individuals, rather than as members of a species” because he believes, in classic liberal fashion, that regarding every being as a freestanding entity to be evaluated on its own merits, unmoored from any larger context, is the fairest option.

Unfortunately, this method of analysis fails utterly to take social, systemic, and even species-level factors into account. It’s quite similar to the liberal argument that racism can be ended through simple “colorblindness.” In addition, his only proposed solutions are based on the individual as the primary unit of agency. Actions you can take toward animal liberation include becoming a vegetarian or vegan, avoiding products where animal experimentation is used, and so on, and arguing with others to do the same.

These actions have been ineffective in actually changing the current food system. If you applied this logic to the fight against racism you could avoid racist behaviors, avoid purchasing things from companies with racist practices or policies, or refuse to give your tourist dollars to states or countries with a bad record of racist practices. These individual solutions, however, are ineffective if the goal is to fight racism on a systemic level. Racism is woven into the fabric of US capitalism; boycotts are only effective when they are part of the strategy of a mass movement that directly challenges the systemic nature of racism.

In another interview in the same series, conducted in January 2015, Yancy asks philosopher Judith Butler about the slogan “All Lives Matter.” Yancy notes that white people — the kinds of liberals who “can’t see color” — often espouse “All Lives Matter” whenever the cry goes up that Black Lives Matter.

Do all lives matter? Of course they do — but in a context in which black lives are treated by the police, by the courts, and by the majority of whites as less valuable, the very universality of “All Lives Matter” becomes a mockery, a dismissal of black lives in particular. As Butler puts it:

We cannot have a race-blind approach to the questions: which lives matter? Or, which lives are worth valuing? If we jump too quickly to the universal formulation, “all lives matter,” then we miss the fact that black people have not yet been included in the idea of “all lives.” To make that universal formulation concrete, to make that into a living formulation, one that truly extends to all people, we have to foreground those lives that are not mattering now, to mark that exclusion, and militate against it.

In the same vein, to make purely utilitarian arguments about the worth of the lives of people with disabilities and people of color without regard for the historical context in which such lives have been and still are consistently treated as being of less worth — to pretend that the playing field is level — is, whatever the intent of conclusion of those arguments, itself a form of moral violence.

Of course, there are plenty of good reasons to become a vegetarian, to advocate for better treatment for animals, or to oppose factory farming. At the end of the day, though, the “speciesism” argument, with its false equivalence to racism and its insistence that “animal lives matter,” is simply incompatible with a genuine antiracism.