RESEARCH PAPERS

Gettier's counterexamples and his presuppositions
Sutapa Saha

 

1.1 The traditional definition of knowledge

For no less than two decades the problem of the analysis of knowledge has haunted the minds of the epistemologists. Even in times as early as Plato, philosophers were seen engaged in this problem. Presuming that we are talking about propositional knowledge1 only, we may assert that in all cases of propositional knowledge the analysis has turned up with two or more conditions as the necessary and sufficient conditions of knowing. The follo­wing arc some of the specimens of this analysis2 :
(1)   S knows that p
iff
(i) S accepts that p
(ii) p is true
(iii) S has adequate evidence that p
(2)   S knows that p
iff
(i) S is sure that p
(ii) p is true
(iii) S has the right to be sure that p
(3)   S knows that p
iff
(i) S believes that p
(ii) p is true
(iii) S is justified in believing that p
This analysis has given birth to a huge stock of literature. Some philosophers have got impatient with the indecisive character of this pursuit and has announced the endeavour to be closed and unremunerative. They declare that henceforth attention should be transferred to such questions as What are the sources of justification? What is the nature of justification? etc. They have, however, not omitted the problem of analysis of knowledge altogether but relegated it to a less interesting area of enquiry. But the fact that they could not altogether ignore it indicates the importance of the problem.

The first of the definitions of knowing noted is offered by R. M. Chisholm in Perceiving: A Philosophical Study.3 The second one is provided by A. J. Ayer in The Problem of Knowledge.4 So far as the first condition is concerned, assuming that Chisholm's 'accepts' is not basically different from 'believes' we can say that what Chisholm speaks in terms of acceptance may be said in terms of belief. Again, what Ayer speaks in terms of 'being sure' can be slated in terms of belief, though, as we shall see shortly, one may hold a belief without being sure. So far as the second condition is concerned, there is no difference between the three definitions. For Chisholm, the third condition consists in having adequate evidence for the proposition which is believed. One who merely believes that the fireworks party will be spoiled due to rain cannot be said to know for he has no evidence for the proposition believed. It is also not enough that there be some evidence; the evidence must be strong enough. If the person sees the sky growing dark he may have some evidence for his belief that there will be rain, but the darkness of the sky may be due to cloud of smoke released by the oil storage tanks which are on fire. In this case, there is evidence but it is not adequate enough. One may wonder why Ayer speaks in terms of 'having the right to be sure' and not in terms of having adequate evidence. The reason may be that for some propositions which are known there may be no evidence at all, e.g., the basic empirical propositions and the self-evident a priori propositions. Further, for some other type of propositions which are known, there may be no evidence at all. To quote Ayer: "Moreover, we cannot assme that, even in particular instances, an answer to the question How do you know ? will always be forthcoming."5

The third condition of the third definition, however, may be said to accommodate the third condition of the other two defini­tions. If a person has adequate evidence for a proposition p, he may be said to be justified in believing that p. Similarly when a man has the right to be sure that p, he is justified in believing that p. So we choose, as our model of the traditional definition of knowledge, the third definition which is often abbreviated in the literature as JTB analysis of knowing. It includes three condi­tions, viz., the belief condition, the truth condition and the justifica­tion condition. Each of these three conditions is a necessary condition of knowing and jointly they are sufficient.

 


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