Gettier problem

1. Gettier-type cases

Clarifying the Gettier problem as most philosophers have seen it (‘How can the standard analyses be altered so that Gettier-type cases do not constitute counterexamples to the modified analyses, and without opening the analyses to further objections?’) involves clarifying the terms ‘a standard analysis’ and ‘Gettier-type cases’. We may here sidestep concern with the former (but see Shope 1981) by rephrasing the problem as: ‘What aspect of a correct analysis of one’s knowing that p prevents Gettier-type cases from constituting counterexamples to it?’ Philosophers who adopt the broadest perspective regard a Gettier-type case as any situation where justified, true believing falls short of knowing. Others are influenced by the manner in which they expect the central problem to be resolved. For example, those who think that the counterexamples in question can be avoided by clauses in a correct analysis ruling out the falsity of specific types of propositions to which the knower is related will characterize Gettier-type cases as situations where knowledge is absent because various propositions are false. Those who hope to avoid the counterexamples by strictures on the durability or degree of justification of one’s believing that p may prefer to define ‘Gettier-type case’ by mentioning aspects of such justification. Alternatively, Alvin Plantinga (1993b) suggests that Gettier-type cases involve a slight mismatch between the proper functioning of one’s cognitive equipment and one’s circumstances.

Approaches to resolving the central problem have been too multifarious for a brief summary. So, setting aside differences over what constitutes an analysis (Shope 1981, and forthcoming), consider how variations on the following important Gettier-type case (Lehrer 1965) impact on a number of prominent attempts to analyse knowing:

This case differs slightly from one of Gettier’s original (1963) examples, in which one notices that by picking at random a city name such as ‘Barcelona’, one can deduce from the unsuspectedly false proposition that f′, ‘Jones owns a Ford’, the conclusion that p′, ‘Either Jones owns a Ford or Brown is in Barcelona’, which one proceeds to believe on the grounds of the proposition that f′.

In Gettier’s other original example, one justifiably believes the unsuspectedly false proposition that f″: ‘Jones, who is not myself, is the man who will get the job, and Jones has ten coins in his pocket’, and one sees that it entails that p″: ‘The man who will get the job has ten coins in his pocket’, which one then believes on the grounds of the proposition that f″. Unsuspectedly, not only does one have ten coins in one’s own pocket, but it is oneself who is going to get the job.

Some variants of the Nogot case do not involve one’s having relevant false beliefs. (Indeed, Gettier only spoke of a proposition as the basis for one’s inferring that p′ [that p″].) For instance, one may happen to be a clever and cautious reasoner not interested in who owns a Ford but only in whether it is true that p, and realizing that someone in the office other than Nogot might happen to own a Ford, one decides that it is safer merely to accept that p than to believe that f (see Lehrer 1974). Alternatively, Richard Feldman (1974) has noted that one may not arrive at a belief that p by relying upon considerations about the proposition that f, but instead by utilizing as a basis for believing that p the following true existential generalization of one’s evidence: ‘There is someone in the office who has provided me with evidence e‘.