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Gettier Cases, Warranted Assertability Maneuvers, and the Fourth Condition

Tomasz Puczyłowski


In this paper I present a warranted assertability maneuver (WAM) and three necessary criteria for its rational applications proposed by Keith DeRose. I show that these criteria are not sufficient to reject a WAM directed against Gettier’s famous cases, for it satisfies all the criteria. If the WAM against Gettier’s claim is correct, then Gettier’s argumentation is less persuasive and conclusive than it has seemed before and it becomes questionable. If one were to insist that the Gettier cases truly showed that the traditional definition of knowledge was too broad and should not be explained in terms of generating false conversational implicatures by true assertions of Gettier’s sentences, then one would have to conclude that there should be some other unidentified by DeRose criteria which were not satisfied by the WAM in Gettier case discussion. Therefore I propose the fourth standard for successful WAM: If in a context C the assertion of sentence S is unacceptable only because it generates some false conversational implicatures I1,…, In, then the assertion of S in any other context C* generating false I1,…, In is unacceptable to the same extent as the assertion of S in C.

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