Peter Singer

Singer was born in Melbourne to Jewish parents who had fled Vienna; three of his grandparents died in Nazi camps. He studied law, history and philosophy at Melbourne and went to Oxford in 1969 to work under the utilitarian R. M. Hare, writing his B.Phil. thesis on civil disobedience. At Oxford he met a vegetarian graduate student and asked why he did not eat meat; the conversation changed his life, and in 1973 he published 'Animal Liberation' in the New York Review of Books, expanded into a book in 1975.

Animal Liberation argues that the interests of any being that can suffer deserve equal consideration, and that disregarding suffering merely because of species is 'speciesism', logically parallel to racism and sexism. The book exposed factory farming and animal experimentation and became the bible of the animal rights movement, though he himself speaks of interests, not rights. 'Famine, Affluence, and Morality' (1972) gave the drowning child argument: if you pass a pond and see a child drowning, you are obliged to wade in at the cost of your clothes; distance and numbers do not change that obligation, so the affluent are obliged to give most of their wealth to relieve distant poverty.

Practical Ethics (1979) treated abortion, euthanasia, animals, poverty and the environment systematically. His view that parents and doctors may in some cases choose to let severely disabled newborns die led protesters to shut down his lectures in Germany and Austria, and his appointment as professor of bioethics at Princeton in 1999 provoked demonstrations. His position is consistent: what matters is sentience and interests, not membership of the species 'human'. From 1977 he taught at Monash University, where he founded the Centre for Human Bioethics.

The Life You Can Save (2009) and The Most Good You Can Do (2015) drove the effective altruism movement: use evidence and reason to find where each dollar does the most good and give away a substantial share of income; he gives away forty per cent of his own. He and his wife have been vegetarian for decades, he has stood for the Australian Greens, and on winning the Berggruen Prize in 2021 he gave away the entire million dollars. He still teaches at Princeton and Melbourne and hosts a podcast, one of the few philosophers who have turned arguments directly into social movements.