<philosophical terminology> the sentence "I am now lying" would seem to be true (because I am lying) only in those cases when it is false (since what I say is the case) and false (because I am not lying) when it is true (since what I say is not the case). Less personally, the statement "This sentence is not true" generates a similar perplexity. These are particular instances of the self-referential semantic paradoxes that have troubled logicians since Epimenides, the Cretan who is supposed to have said, "All Cretans are liars." Recommended Reading: Paradox of the Liar, ed. by Robert L. Martin (Ridgeview, 1979); Recent Essays on Truth and the Liar Paradox, ed. by Robert L. Martin (Oxford, 1997); Vann McGee, Truth, Vagueness, and Paradox: An Essay on the Logic of Truth (Hackett, 1990); Robert C. Koons, Paradoxes of Belief and Strategic Rationality (Cambridge, 1992); and Benson Mates, Skeptical Essays (Chicago, 1981).
[A Dictionary of Philosophical Terms and Names]
<logic> A sentence which asserts its own falsity, e.g. "This sentence is false" or "I am lying". If it is true, then it is false; if it is false, then it is true. Also called the Epimenides paradox. ["The Liar: an Essay on Truth and Circularity", Jon Barwise and John Etchemendy, Oxford University Press (1987). ISBN 0-19-505944-1 (PBK), Library of Congress BC199.P2B37].
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