Peter Singer (born 1946) is an Australian moral philosopher whose work has significantly shaped contemporary debates in applied ethics, bioethics, and social philosophy. He is widely regarded as one of the most influential utilitarian thinkers of the modern era. Educated at the University of Melbourne and later at the University of Oxford, Singer has held academic positions in Australia, the United Kingdom, and the United States, including a long-standing appointment at Princeton University.
Singer first came to prominence with the publication of Animal Liberation in 1975, a work that helped establish the modern animal rights movement. In this book, he argued that the interests of non-human animals should be given equal consideration to those of humans, based on their capacity to suffer. This position led him to criticize factory farming, animal experimentation, and other practices that inflict unnecessary harm. Singer’s advocacy contributed to significant shifts in public attitudes and academic discourse concerning animal welfare.
His ethical framework is grounded in preference utilitarianism, a form of consequentialism that evaluates actions according to their ability to satisfy the preferences of all affected parties. Singer has applied this principle to a wide range of moral questions, including euthanasia, global poverty, and medical ethics. His book Practical Ethics (1979) systematically addresses these issues and has become a standard text in university ethics courses.
Singer is also a leading figure in the effective altruism movement, which promotes using evidence and reason to direct resources toward the most impactful solutions to global problems. In The Life You Can Save (2009), he argues that affluent individuals have a moral obligation to assist those living in extreme poverty, outlining practical ways to achieve this.
Singer’s views have attracted both support and controversy, particularly his positions on infanticide, disability, and end-of-life decisions. Despite these debates, his influence on applied ethics, public policy, and moral philosophy remains considerable, making him one of the most widely read and debated philosophers of the late twentieth and early twenty-first centuries.