The story
Named after the logician and philosopher Charles Sanders Peirce.
Etymology from Wiktionary, CC BY-SA 4.0.
Peirce's law
Today it means: The classically valid but intuitionistically non-valid formula ((P→Q)→P)→P of propositional calculus, which can be used as a substitute for the law of excluded middle in implicational propositional calculus. Full definition →