Earliest Uses of Symbols of Set Theory and LogicEarliest Uses of Symbols of Set Theory and Logic Last updated: Oct. 8, 2019 The study of logic goes back more than two thousand years and in that time many symbols and diagrams have been devised. Around 300 BC Aristotle introduced letters as term-variables, a "new and epoch-making device in logical technique." (W. & M. Kneale The Development of Logic (1962, p. 61). The modern era of mathematical n
