Hostname: page-component-76fb5796d-25wd4 Total loading time: 0 Render date: 2024-04-26T13:50:00.098Z Has data issue: false hasContentIssue false

Do You Know Everything That You Know?

Published online by Cambridge University Press:  01 January 2020

Steven R. Levy*
Affiliation:
University of California, Riverside

Extract

In the ongoing attempt to provide a satisfactory analysis of knowledge numerous conditions have been proposed as necessary and sufficient — the most noteworthy being justification, truth, and belief. In addition, various epistemic principles are frequently employed. In this paper I intend to show how the seemingly innocuous justification condition, along with two relatively uncontroversial epistemic principles, can give rise to a paradoxical situation.

Type
Research Article
Copyright
Copyright © The Authors 1979

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 In Belief, Truth and Knowledge (Cambridge, 1973), p. 186.Google Scholar

2 Of course it may be rational for S to believe something that he does not, in fact, believe (perhaps he has never thought about it). So the satisfaction of the antecedent of [1) does not entail that S believes that (p & q … )-only that such a belief would be rational. Throughout this discussion we shall also make the usual additional assumptions required by epistemic principles such as [1): (1) that S understands the logical entailment between the components of a conjunction and the conjunction itself, (2) that S correctly deduces the conjunction as a result of his understanding of the entailment, and (3) that S believes the conjunction as a result of (1) and (2). At certain points in the discussion we shall stop short of making the third assumption for reasons that will become obvious.

3 See, e.g., Kyburg, H. E., Probability and the Logic of Rational Belief (Middletown, 1961).Google Scholar

4 Op. cit., p. 139.

5 A similar point was made by Goldman, Alan H., “A note on the conjunctivity of Knowledge,” Analysis (1975).CrossRefGoogle Scholar

6 Keith Lehrer makes a related observation in “When Rational Disagreement is Impossible,” Nous (1976).

7 With the supposition stated in this way, the counterexample works when modified so as to omit question 4 from the examination but to allow that S rationally believes that he does not know everything that he thinks he knows.

8 Op., cit.

9 See, for example, Goldman, Alvin, “Discrimination and Perceptual Knowledge,” journal of Philosophy (1976).CrossRefGoogle Scholar Goldman's analysis there is on the right track although it suffers because it contains a condition similar to a defeasibility requirement. I have examined such requirements in depth in “Defeasibility Theories of Knowledge,” Canadian journal of Philosophy (1977), and in “Misleading Defeaters,” The journal of Philosophy (1978).