Edward John Lemmon (1 June 1930 – 29 July 1966) was a British logician and philosopher born in Sheffield, England.
Lemmon attended King Edward VII School[1] in Sheffield until 1947, before reading Literae humaniores at Magdalen College, Oxford, as an undergraduate, and was appointed Fellow of Trinity College, Oxford, in 1957.
John Lemmon became interested in modal logic when Arthur Prior visited Oxford University in 1956 to give the John Locke lectures, later published as his Time and Modality (Prior 1957).
Prior returned for twelve months soon after, to lead a small group including Lemmon, Peter Geach and Ivo Thomas (Copeland 2004).
John Lemmon became one of the early champions of Prior's distinctive approach to tense logic, and Lemmon's later work on alethic modality and applications of modal logic to ethics bear the mark of Prior's influence.