From Ignorance to Irrationality

Peter Unger

in Ignorance

Published in print January 1978 | ISBN: 9780198244172
Published online November 2003 | e-ISBN: 9780191711473 | DOI:

Series: Clarendon Library of Logic and Philosophy

 From Ignorance to Irrationality

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Defends the claim that skepticism about knowledge entails skepticism about rationality. It argues that if anybody is ever justified or reasonable in believing anything, then he or she must know something to be so. Hence, if nobody can ever know anything, nobody can ever be justified or reasonable in believing anything either. This argument is supported by considerations about the entailments of sentences of the form “S's noun is that p.” Even if only a limited form of skepticism about knowledge is endorsed, the chapter argues, the principle that it should be possible for one to know one's reasons yields a far‐reaching skepticism about rationality.

Keywords: entailment; justification; knowledge; nouns; rationality; reasons

Chapter.  23028 words. 

Subjects: Metaphysics

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