RI Gettier Problem 2023

RI KI Y5 Knowledge & Justification: JTB 1 Reading: The Gettier Problem Before Gettier's essay below was published, most analytic philosophers took it for granted that something we might call the JTB account of knowledge was correct. The JTB account claims that knowledge can be conceptually analyzed as justified true belief. But Gettier came along and seriously called JTB into question. See if you agree with him. Edmund Gettier currently teaches at the University of Massachusetts. Gettier Is Justified True Belief Knowledge? Edmund L. Gettier From Analysis 23 ( 1963): 121-123. Transcribed into hypertext by Andrew Chrucky, Sept. 13, 1997. Various attempts have been made in recent years to state necessary and sufficient conditions for someone's knowing a given proposition. The attempts have often been such that they can be stated in a form similar to the following:1 a. S knows that P IFF i. P is true, ii. S believes that P, and iii. S is justified in believing that P. For example, Chisholm has held that the following gives the necessary and sufficient conditions for knowledge:2 b. S knows that P IFF i. S accepts P, ii. S has adequate evidence for P, and iii. P is true. Ayer has stated the necessary and sufficient conditions for knowledge as follows:3

RI KI Y5 Knowledge & Justification: JTB 2 c. S knows that P IFF i. P is true, ii. S is sure that P is true, and iii. S has the right to be sure that P is true. I shall argue that (a) is false in that the conditions stated therein do not constitute a sufficient condition for the truth of the proposition that S knows that P. The same argument will show that (b) and (c) fail if 'has adequate evidence for' or 'has the right to be sure that' is substituted for 'is justified in believing that' throughout. I shall begin by noting two points. First, in that sense of 'justified' in which S's being justified in believing P is a necessary condition of S's knowing that P, it is possible for a person to be justified in believing a proposition that is in fact false. Secondly, for any proposition P, if S is justified in believing P, and P entails Q, and S deduces Q from P and accepts Q as a result of this deduction, then S is justified in believing Q. Keeping these two points in mind, I shall now present two cases in which the conditions stated in (a) are true for some proposition, though it is at the same time false that the person in question knows that proposition. Case I Suppose that Smith and Jones have applied for a certain job. And suppose that Smith has strong evidence for the following conjunctive proposition: d. Jones is the man who will get the job, and Jones has ten coins in his pocket. Smith's evidence for (d) might be that the president of the company assured him that Jones would in the end be selected, and that he, Smith, had counted the coins in Jones's pocket ten minutes ago. Proposition (d) entails: e. The man who will get the job has ten coins in his po