, Volume 184, Issue 3, pp 247–259 | Cite as

Is knowledge justified true belief?

  • John TurriEmail author


Is knowledge justified true belief? Most philosophers believe that the answer is clearly ‘no’, as demonstrated by Gettier cases. But Gettier cases don’t obviously refute the traditional view that knowledge is justified true belief (JTB). There are ways of resisting Gettier cases, at least one of which is partly successful. Nevertheless, when properly understood, Gettier cases point to a flaw in JTB, though it takes some work to appreciate just what it is. The nature of the flaw helps us better understand the nature of knowledge and epistemic justification. I propose a crucial improvement to the traditional view, relying on an intuitive and independently plausible metaphysical distinction pertaining to the manifestation of intellectual powers, which supplements the traditional components of justification, truth and belief.


Knowledge Gettier problem Epistemic justification Manifestation Stephen Hetherington Brian Weatherson 


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© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.University of WaterlooWaterlooCanada

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