Bentham defined as the “fundamental axiom” of his philosophy the principle that “it is the greatest happiness of the greatest number that is the measure of right and wrong”. He became a leading theorist in Anglo-American philosophy of law, and a political radical whose ideas influenced the development of welfarism. He advocated for individual and economic freedoms, the separation of church and state, freedom of expression, equal rights for women, the right to divorce, and the decriminalising of homosexual acts. He called for the abolition of slavery, of the death penalty, and of physical punishment, including that of children. He has also become known as an early advocate of animal rights. Though strongly in favour of the extension of individual legal rights, he opposed the idea of natural law and natural rights (both of which are considered “divine” or “God-given” in origin), calling them “nonsense upon stilts”. Bentham was also a sharp critic of legal fictions.
Bentham’s students included his secretary and collaborator James Mill, the latter’s son, John Stuart Mill, the legal philosopher John Austin, as well as Robert Owen, one of the founders of utopian socialism. He “had considerable influence on the reform of prisons, schools, poor laws, law courts, and Parliament itself.”