In order for knowledge to be knowledge, does it have to be true, or in other words, when something that everyone today believes to be true turns out to be wrong next year, was it not knowledge?
Thetraditional account of knowledge is that truth is one of three necessaryconditions for knowledge. The other two are belief and justification. On thisaccount, if X knows that p, then (1) X believes that p, (2) X is justified inbelieving p, and (3) p is true. Thus if a widely held justified beliefturned out to be false, then the belief would not count as knowledge. Of course there is much work to be done inspelling out what we are to understand by belief, justification, and truth. A great deal ofattention to this definition and the question of its adequacy followed EdmundGettier’s paper “Is Justified True Belief Knowledge?” ( Analysis 23 ( 1963): 121-123; available online at http://www.ditext.com/gettier/gettier.html )