Peter Singer

Early Life and Education

Peter Albert David Singer was born on July 6, 1946, in Melbourne, Australia, to Jewish parents who had emigrated from Vienna to escape the Nazi regime. Three of his grandparents died in the Holocaust. He studied law and philosophy at the University of Melbourne before moving to Oxford for graduate work, where he completed his B.Phil. in 1971 under the supervision of R.M. Hare, whose prescriptivist metaethics and preference utilitarianism significantly influenced Singer's approach.

Animal Liberation (1975)

Animal Liberation (1975), sometimes called "the bible of the animal rights movement," was Singer's breakthrough work. Drawing on Bentham's principle that the capacity to suffer, not the ability to reason, is the relevant criterion for moral consideration, Singer argued that the practice of treating animals differently from humans merely because of their species — which he termed "speciesism" — is a form of discrimination analogous to racism and sexism.

Singer did not argue for "animal rights" in the strict sense (he is a utilitarian, not a rights theorist) but for the equal consideration of interests: the suffering of any sentient being deserves equal weight regardless of species. The book documented the systematic cruelty of factory farming and animal experimentation, providing both the philosophical framework and the factual basis for the modern animal welfare movement.

Practical Ethics and Global Poverty

Practical Ethics (1979, revised 1993, 2011) became one of the most widely used textbooks in applied ethics. It extended Singer's utilitarian framework to questions of abortion, euthanasia, infanticide, global poverty, environmental ethics, and the treatment of refugees.

Singer's essay "Famine, Affluence, and Morality" (1972) presented a deceptively simple but radically demanding argument: if it is in our power to prevent something bad from happening without sacrificing anything of comparable moral importance, we ought to do it. Since the affluent can prevent suffering and death from poverty without comparable sacrifice, they are morally obligated to do so. This argument implies that the way most affluent people live — spending on luxuries while others die of preventable causes — is morally indefensible.

This line of reasoning eventually gave rise to the effective altruism movement, which Singer championed in The Life You Can Save (2009) and The Most Good You Can Do (2015). Effective altruism applies evidence and reason to determine the most effective ways to improve the world.

Bioethics and Controversy

Singer's utilitarianism has led him to positions that have generated intense controversy. He has argued that in some cases, euthanasia of severely disabled newborns can be morally permissible, that the traditional sanctity of human life ethic is untenable, and that the moral status of a being depends on its actual capacities (particularly self-awareness and the capacity to have preferences about the future) rather than its species membership.

His appointment to a professorship at Princeton in 1999 generated significant protests, particularly from disability rights groups. Singer has engaged with these critiques while maintaining that utilitarian reasoning, consistently applied, requires abandoning species-based moral distinctions.

Singer has held positions at Monash University and Princeton University, where he is the Ira W. DeCamp Professor of Bioethics. He has been named one of the most influential people alive by Time magazine and is widely regarded as the world's most influential living philosopher.