Leslie, John

John Leslie (1940-2022) was a British-Canadian philosopher who made significant contributions to cosmology, philosophical theology, and the anthropic principle. Educated at Oxford, he spent most of his career at the University of Guelph. Leslie developed influential arguments about fine-tuning and divine creation, proposing that the universe exists because of an ethical requirement for its existence. His major works include "Value and Existence" (1979) and "Universes" (1989), which advanced a neo-Platonic vision where God is understood as the creative ethical requirement that good things exist. In "Immortality Defended" (2007), Leslie argued for the possibility of afterlife through a distinctive philosophical framework combining Platonic idealism with modern physics. His work uniquely bridged analytic philosophy of religion with cosmological speculation, offering sophisticated defenses of both theistic and pantheistic worldviews.