Edwards was born Paul Eisenstein in Vienna in 1923 to assimilated Jewish parents, the youngest of three brothers. According to Peter Singer, his upbringing was non-religious. He distinguished himself early on as a gifted student and was admitted to the Akademisches Gymnasium, a prestigious Viennese high school. When Germany annexed Austria in 1938, Edwards was sent by his family to Scotland, later joining them in Melbourne, Australia, where the family name was changed to Edwards. He attended Melbourne High School, graduating as dux of the school, then studied philosophy at the University of Melbourne, completing a B.A. and M.A.