Peter Singer

Peter Singer

: Photo from Wikimedia Commons / Author of Photo: TimVickers


* Professor of bioethics
* Founder of the modern animal-rights movement
* Believes that animals have just as much inherent value as human beings
* Characterizes the denial of animals’ basic “rights” as “speciesism,” comparable to racism and sexism
* Likens the animal-rights movement to the abolition movement and the WWII-era fight against Hitler

Peter Singer was born on July 6, 1946 in Melbourne, Australia, the son of Austrian Jews who had fled Nazi-occupied Vienna in 1938. He attended Scotch College in Victoria before transferring to the University of Melbourne, where he earned both a B.A. and an M.A. in philosophy (in 1967 and 1969, respectively). He then obtained a B.Phil. Degree at Oxford University in 1971.

After completing his formal schooling, Singer served as: a Radcliffe Lecturer at Oxford’s University College from 1971-73; a Visiting Assistant Professor in New York University’s Department of Philosophy from 1973-74; a Senior Lecturer in La Trobe University’s Department of Philosophy from 1975-76; a Professor of Philosophy at Monash University from 1977-99; and a full-time Ira W. DeCamp Professor of Bioethics at Princeton University‘s Center for Human Values from 1999-2004. Since 2005 he has been a part-time Professor at Princeton University and the University of Melbourne. For additional details about Singer’s academic career, click here.

Singer’s philosophy can be classified as utilitarianism, and his influence in the academic world has been immense. National Review has called him “the most celebrated bioethicist and moral philosopher of our times.”American Thinker notes that his writings “are a constant staple in literary and ethics texts used in American universities.” In 2005 Singer was named byTime magazine as one of the world’s 100 “most influential people.” And in 2009 The Sydney Morning Herald and The Age listed him as one of the 25 most influential Australians of the last half-century.

Animal Liberation

In 1975 Singer authored Animal Liberation, a landmark book that effectively launched the modern animal-rights movement. In this volume, he contends that people should recognize and respect the moral worth of all animals—not because of whatever level of intelligence the various species may possess, but rather, because of their ability to experience pain and suffering. Singer characterizes the denial of animals’ basic “rights” as a form of discrimination called “speciesism,” comparable to racism and sexism.

Deeming it wrong to assign a greater inherent value to human beings than to any other form of animal life, Singer (in Animal Liberation) rejects the biblical notions that mankind was created to be nature’s steward or master; that humans have souls but animals do not; and that people are made uniquely in the image of God. “All three [of the foregoing axioms] taken together do have a very negative influence on the way in which we think about animals,” Singer says, explaining that his mission is to challenge “this superiority of human beings.” He implores humans to “extend to other species the basic principle of equality that most of us recognize should be extended to all members of our own species”

Also inAnimal Liberation, Singer considers whether there is moral justification for anyone to “break in and free the animals” that are caged in laboratories where they are destined to serve as the subjects of medical experiments. “That [the act of releasing the animals] is illegal,” he acknowledges, “but the obligation to obey the law is not absolute. It was justifiably broken by those who helped runaway slaves in the American South.” Throughout Singer’s text, the animal-rights crusade is likenedto the abolition movement of the 1800s and the fight against Hitler in the 1940s.

Singer rejects, as “medieval,” “the notion that human life is sacred just because it is human life.” “Why should all members of the species homo sapiens have a right to life and other species not?” he asked rhetorically in a 2015 interview. “This idea arises only [from] our religious heritage. We have been taught for centuries that man was created in the image of God, that God has given us dominion over the animals, and that we have immortal souls.”

Singer’s compassion for animals led him to become a vegetarian in 1971. More recently, he has become a self-identified vegan. Asserting that “no one has the right to inflict needless suffering on another sentient being,” Singer maintains that “no one with access to a wide range of food needs to eat meat.”

The Right to Kill Infants & the Mentally Impaired

Singer maintains that because infants are not intellectually self-aware, they are not yet “persons” in the full sense of the term, and thus they have less intrinsic value than those who possess such awareness. In other words, the killing of infants is not necessarily objectionable from a moral perspective. In his 1996 book Rethinking Life and Death, Singer wrote: “Since neither a newborn infant nor a fish is a person, the wrongness of killing such beings is not as great as the wrongness of killing a person.”

By Singer’s reckoning, this principle is even more certain in cases that involve infants with handicaps and disabilities. In his 1979 book Practical Ethics, for example, he contends, that human parents should be legally permitted to kill their infant child if, at any time during its first 28 days of life, they deem it unworthy of preservation due to some serious handicap or abnormality. By Singer’s reckoning, infants with severe disabilities (such as Down Syndrome or hemophilia) are “replaceable” in the sense that their families are ultimately better off ridding themselves of such emotionally, physically, and financially burdensome youngsters: “When the death of a disabled infant will lead to the birth of another infant with better prospects of a happy life, the total amount of happiness will be greater if the disabled infant is killed.” Elsewhere, Singer puts it this way: “There are some circumstances …where the newborn baby is severely disabled and where the parents think that it’s better that that child should not live, when killing the newborn baby is not at all wrong.” And on another occasion, he said that “killing a defective infant is not morally equivalent to killing a person.”

In 2006 a woman asked Singer pointedly, “Would you kill a disabled baby?” He replied, “Yes, if that was in the best interests of the baby and of the family as a whole. Many people find this shocking, yet they support a woman’s right to have an abortion.” “[F]rom the point of view of ethics rather than the law,” Singer added, “there is no sharp distinction between the fetus and the newborn baby.”

Singer’s reasons for favoring the termination of disabled infants’ lives are rooted not only in his particular brand of ethics, but also in his own financial considerations. “I don’t want my health insurance premiums to be higher so that infants who can experience zero quality of life can have expensive treatments,” says Singer.

In a related matter, Singer would not find it morally objectionable if parents were permitted to conceive children specifically for the purpose of harvesting their organs for transplant into an older child who may need them. And on a macro level, he similarly endorses the prospect of a society that actively breeds large numbers of children to serve, essentially, as sources of spare body parts for other youngsters.

The Relative “Worth” of Animals vs. People

Singer gives extensive attention to the question of the relative worth of animals vs. humans (with varying degrees of intellectual and physical capacity) in his book Animal Liberation: “Adult chimpanzees, dogs, pigs, and members of many other species far surpass the brain-damaged infant in their ability to relate to others, act independently, be self-aware, and any other capacity that could reasonably be said to give value to life. … The only thing that distinguishes the infant from the animals, in the eyes [of those] who claim it has a right to life, is that it is biologically a member of the species Homo sapiens…. But to use this difference as the basis for granting a right to life to the infant and not to other animals is, of course, pure speciesism. It is exactly the kind of arbitrary difference that the most crude and overt kind of racist uses in attempting to justify racial discrimination.”

In Singer’s view, it is not only infants—but all people of any age who have a mental impairment that limits their “capacity to think, relate and experience”—who are not “persons” in the full sense of the term, and who thus have less intrinsic value than those who are not impaired. In other words, neither the killing of infants nor of the mentally impaired is necessarily objectionable from a moral perspective: “[W]e should not see all human lives as of equal worth but recognize that some are more valuable than others.” Proceeding from that premise, Singer advocates the use of disabled people as subjects in medical experiments. Indeed, when _Psychology Today_asked him to comment on the fact that the development of the hepatitis vaccine had been made possible by experiments performed on chimpanzees, Singer said that such research should instead use disabled humans as its subjects. On another occasion, he suggested that animals and disabled humans were of essentially equal worth: “An animal experiment cannot be justifiable unless the experiment is so important that the use of a brain-damaged human would be justifiable.”

Singer favors euthanasia for people who, through injury or disease, have lost significant physical and mental capacities, and thus their personhood, saying: “Some humans are non-persons, while some non-human animals are persons…. We put a horse that has broken its leg out of its misery as quickly as possible. This merciful act spares the animal an untold amount of needless suffering. If we look upon human animals in the same fashion, our opposition to killing those who are suffering will begin to dissolve.” “In cases of brain damage making it impossible for the patient to express a preference,” Singer adds, “this principle obviously opens the door to non-voluntary euthanasia.” Such a course of action, he explains, would allow families to “move on” from a time of deep emotional distress.

An interviewer once asked Singer what he would do in a situation where he had an opportunity to rescue either a human being or a mouse—but not both—from a burning building. He replied: “… [I]n almost all cases I would save the human being. But not because the human being is human … Species membership alone isn’t morally significant … The qualities that are ethically significant are, firstly, a capacity to … feel pain, or to have any kind of feelings. That’s really basic, and it’s something that a mouse shares with us. But when it comes to a question of taking life, or allowing life to end, it matters whether a being … can see that he or she actually has a life … Such a being has more to lose than a being incapable of understanding this…. So normally, the death of a human being is a greater loss to the human than the death of a mouse is to the mouse … But this depends on the qualities and characteristics that the human being has. If, for example, the human being had suffered brain damage so severe as to be in an irreversible state of unconsciousness, then it might not be better to save the human.”

Similarly, in a 2015 interview Singer was asked: “If you were standing in front of a burning house, where 200 pigs and a child, and you could save either the animals or the child, what would you do?” He answered: “The suffering of animals at some point so great that you should decide to free the animals and not the child. Whether this point is reached at 200 or two million animals, I do not know. But one must not be burned countless animals in order to save a child’s life.”

On yet another occasion, Singer said that, if required to take the lives of either cows or humans, he would kill ten cows before killing one human—not because cows are of any less value, but rather because the human (if he or she were intellectually “normal”) would mourn his or her own fate: “I’ve written that it is much worse to kill a being who is aware of having a past and a future, and who plans for the future. Normal humans have such plans, but I don’t think cows do.”


Singer suggests that the use of genetic engineering to enhance children’s physical and mental capacities is no more objectionable, from a moral standpoint, than giving youngsters expensive, cutting-edge educational toys “to maximize their learning potential.” Genetic manipulation, he expands, would be especially acceptable if carried out in a free society rather than in an autocracy:

“Many will condemn this as a resurgence of ‘eugenics,’ the view, especially popular in the early twentieth century, that hereditary traits should be improved through active intervention. So it is, in a way, and in the hands of authoritarian regimes, genetic selection could resemble the evils of earlier forms of eugenics, with their advocacy of odious, pseudo-scientific official policies, particularly concerning ‘racial hygiene.’ In liberal, market driven societies, however, eugenics will not be coercively imposed by the state for the collective good. Instead, it will be the outcome of parental choice and the workings of the free market.”

Singer is troubled, however, by the possibility that in an economically free society—where there is bound to be a certain degree of income inequality—there could exist a situation “where the rich can buy the genes they want and the poor can’t.” “I don’t think that’s the society that would be best in promoting the happiness of most of its members,” he says. “But I’m not convinced it would be a problem if these services were available to everyone.” In other words, Singer views big government—empowered to redistribute wealth and allocate healthcare services—as the solution.

Moreover, it should be noted that Singer has no real objection to the prospect of some parents choosing to abort their fetus or kill their infant child simply because the offspring is physically unattractive: “If everyone had the opportunity to avoid having an ugly child, I don’t think I would have a problem.” When asked whether it might be unwise to permit parents to terminate a new life for so frivolous a cause, he assured: “Most parents are not going to do that. Most parents who go through pregnancy, and childbirth, are going to love and cherish that child.”

Health Care Rationing

Writing in the July 15, 2009 edition of The New York Times, Singer said that “some form of health care rationing”—controlled by government bureaucrats—“is both inescapable and desirable.” Specifically, he lauded the “Quality Adjusted Life Year” (QALY) metric that has long been used by the United Kingdom’s socialized National Health Service. QALY bureaucrats: (a) place a numeric value on one year of each patient’s life—based on the person’s age as well as his or her existing and projected “quality of life”; (b) consult Comparative Effectiveness Research (CER) data vis-a-vis which medications and treatments tend to work best for which medical conditions; and (c) determine whether the costs related to such medicines or treatments can be justified for the patient in question. This approach strongly favors younger patients—who stand to gain the most additional years of “quality” life from various medical treatments—over older patients. As a National Review analysis puts it, “QALYs give greater value to the lives of the able-bodied and young than to people with disabilities and the elderly (which are ‘adjusted’ down based on low ‘quality’) when determining whether the cost of a treatment is worth the price.” Similarly, Human Events explains: “If a teenager can be expected to live another 70 years, saving her life counts as a gain of 70 life-years, whereas if a person of 85 can be expected to live another 5 years, then saving the 85-year-old will count as a gain of only 5 life-years.”


Singer has suggested that the practice of bestiality has remained unacceptable in most cultures because it is not procreative. But because humans engage in all manner of sexual activities with one another that do not lead to conception, he reasons, sex with animals should not be singled out as a forbidden offense—particularly in light of his belief that humans themselves are animals: “…[T]here are many ways in which we cannot help behaving just as animals do—or mammals, anyway—and sex is one of the most obvious ones. We copulate, as they do. They have penises and vaginas, as we do, and the fact that the vagina of a calf can be sexually satisfying to a man shows how similar these organs are.” On another occasion, Singer put it this way: “We are great apes. This does not make sex across the species barrier normal, or natural, whatever those much-misused words may mean, but it does imply that it ceases to be an offence to our status and dignity as human beings.” And while he notes that inter-species intercourse can sometimes have bad physical consequences—e.g., sex between a human male and a hen will likely result in the death of the latter—Singer nonetheless wonders if that is any “worse than what egg producers do to their hens all the time.”

In 2001 Singer wrote a positive review of Midas Dekkers’s book Dearest Pet: On Bestiality, which examines the history of that practice and concludes that the proscription against sex with animals is nothing more than a vestigial “taboo” from an era of sexual repression.


Singer does not object to the practice of necrophilia—provided the deceased gave explicit consent when still alive.

Global Warming

Singer does not balk at NASA scientist James Hansen‘s invocation of Holocaust-related images—such as boxcars and crematoria—in his (Hansen’s) assertion that modern-day coal trains are agents of death which condemn “uncountable irreplaceable species” to extinction. “Given the facts about global warming,” says Singer, “that seems to be exactly what continuing to burn coal will do, as long as we use existing technologies that mean that burning goal contributes to, and will accelerate, climate change. So while the image [of the Holocaust] is vivid and unsettling, I don’t find it objectionable.”

Capitalism & Competition, vs. “Cooperation”

Singer maintains that in order to live a “morally decent life,” no one should keep any wealth beyond what covers his or her barest necessities so long as anyone, anywhere, is in need. In a similar vein, Singer’s 1972 essay “Famine, Affluence, and Morality” argues that it is morally indefensible for an affluent society not to earmark a portion of its wealth for the poor, both at home and abroad.

In 2000 Singer publishedthe book A Darwinian Left: Politics, Evolution and Cooperation, wherein he claims that for too long the theories of social Darwinism have been used by the political “right” to justify capitalism, and even to explain why some societies are prosperous and others are poor. In his book, Singer suggests that Western culture’s emphasis on “competition” should be replaced by an emphasis on “cooperation” as a goal of human evolution, and that such a shift would not be inconsistent at all with human nature. As a book review in First Things put it:

“Recent Darwinians have shown that humans are hard-wired by natural selection for cooperative as well as competitive behavior, even for altruism. Singer cites now-familiar studies of kin altruism, where apparently sacrificial behavior on the part of a mother for her child is ‘explained’ as a strategy for passing on her genes. He also describes game theory experiments showing that cooperative strategies—tit for tat—work best in getting what we want…. [These examples] are enough to satisfy Singer that Darwinism may now be harnessed to support the left’s vision of a more cooperative society.”

While Singer has no strong affinity for free-market economic models, he is by no means blind to their potential real-world benefits, as he made clear in a 2010 interview with the New Left Project: “Capitalism is very far from a perfect system, but so far we have yet to find anything that clearly does a better job of meeting human needs than a regulated capitalist economy coupled with a welfare and health care system that meets the basic needs of those who do not thrive in the capitalist economy. If we ever do find a better system, I’ll be happy to call myself an anti-capitalist.”

In the same interview, Singer said the following about the income and wealth disparities that exist among people everywhere: “There has always been inequality, and there always will be. It goes far deeper than the division between capitalism and socialism. There is inequality among chimpanzees and among flocks of hens. Let’s stop worrying about inequality of wealth and income, and see if we can do something to produce a distribution of income and wealth that leads to less misery and premature death than the present distribution.”

Nine years earlier, in his 2001 book Marx: A Very Short Introduction, Singer was sympathetic to Karl Marx‘s criticism of capitalism, but skeptical about whether a better economic system was likely to arise anytime soon. “Marx saw that capitalism is a wasteful, irrational system,” wrote Singer, “a system which controls us when we should be controlling it. That insight is still valid; but we can now see that the construction of a free and equal society is a more difficult task than Marx realized.”

Singer’s Atheism

Singer rejects the notion that an omnipotent or omniscient divinity is responsible for either the creation, or the ongoing regulation, of the physical universe and its inhabitants. As he wrote in 2008: “Do we live in a world that was created by a god who is all-powerful, all-knowing, and all good? Christians think we do. Yet a powerful reason for doubting this confronts us every day: the world contains a vast amount of pain and suffering. If God is all-knowing, he knows how much suffering there is. If he is all-powerful, he could have created a world without so much of it—and he would have done so if he were all good…. The evidence of our own eyes makes it more plausible to believe that the world was not created by any god at all. If, however, we insist on believing in divine creation, we are forced to admit that the god who made the world cannot be all-powerful and all good. He must be either evil or a bungler.”

Singer’s Views on Israel

In 2002, Singer joined hundreds of Jewish scholars and professionals in signing a petition that called for Israelis to evacuate virtually all of their settlements in Gaza and the West Bank, and to give financial compensation to the Palestinians who resided in those areas. Other signersof the petition included Noam ChomskyStanley HoffmanMichael LernerFrances Fox PivenHarry Targ, and Howard Zinn.

In 2010 Singer signed a petition renouncing his “right of return” to Israel (as the son of Jewish parents), because he viewed the very notion of such a right as “a form of racist privilege that abets the colonial oppression of the Palestinians.”

In June 2012 Singer said, “Clearly, there were moral flaws in the setting up of the State of Israel without proper consultation and participation by Palestinians. But that was a long time ago now, and I think that instead of looking backwards, we should try to work out the best solution for all those living in Israel and the occupied territories.”

Singer has long been a financial supporter Oxfam International, a relief organization that aids populations facing disasters of various sorts (famine, flood, war). One of Oxfam’s chief projects has been its boycott of Israeli products—to protest Israel’s alleged abuse of the Palestinian people. At one time, Singer claimed that he donated 25% of his salary each year to Oxfam.


In 2008 Singer contributed $250 to Barack Obama’s presidential campaign.

Singer himself made a brief foray into the political world in 1996, when he ran, unsuccessfully, as a Green candidate for the Australian Senate.

Additional Information

For additional information on Peter Singer, click here.

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