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Why Margolis Hasn't Defeated the Entailment Thesis

Published online by Cambridge University Press:  01 January 2020

D. S. Mannison*
Affiliation:
University of Queensland

Extract

In two recent papers Joseph Margolis has sketched a situation, his characterisation of which involves a denial of the ubiquitous contention that knowing that p is logically sufficient for believing that p. There are not many philosophers who would follow him in this denial of what is most usually taken as the only “natural” way of construing knowledge. If Margolis has not succeeded in constructing a counterexample to the official view, and I do not believe that he has, it is of some importance to understand just why he has failed. No epistemological gain is achieved by meeting Margolis with a question begging reply, as I think has been done by his critic, J.A. Barker.

The case the Margolis offers is this:

… S may not have thought about P at all, may have thought about Q-which is “significantly” related to P (even, perhaps, by entailment), and believes that Q; on that condition, it is conceivably true that S knows that P (other conditions being satisfied).

Type
Research Article
Copyright
Copyright © The Authors 1976

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References

1 “The Problem of Justified Belief”, Philosophical Studies, 23 (1972); “Alternative Strategies for the Analysis of Knowledge”, Canadian Journal of Philosophy, II (1973).

2 Those few who have expressed doubts about the view that knowledge entails belief include: Radford, ColinKnowledge―by examples”, Analysis, 27 (1966)Google Scholar, Alexander, H.Comments on Saying and Believing”, in Epistemology,(ed.) Stroll, A. Harper & Row, 1967Google Scholar; Vendler, Zeno Res Cogitans, Cornell Univ. Press, 1972Google Scholar, ch. 5; and myself, “ ‘Inexplicable Knowledge’ Does Not Require Belief”, Philosophical Quarterly, April, 1976. Radford's cases involve the assumption of an unformulated and most doubtful causal theory of knowledge; Alexander's treatment seems to confuse what may be false with what may be misleading to say; Vendler's analysis involves a defense of the Platonic thesis that what is known is categorically distinct from what is believed and consequently he is committed to the counter-intuitive position that it is impossible for a to know what b merely believes; and my argument rests on a rather bizarre and unlikely example. As none of the above liabilities seem to be features of Margolis’ case, there is, at least, prima facie reason to think he may have defeated the entailment thesis.

3 “A Note on Knowledge and Belief”, Canadian Journal of Philosophy, vol. V, Sept., 1975. Barker's reply is discussed below.

4 Philos. Studies, op. cit., pp. 405–406.

5 Although Margolis mentions only entailment as being in the domain of “p' s being significantly related to q”, I would take it, and I think Margolis would as well, that p is significantly related to q if p provides adequate epistemic justification for q.

6 op. cit., p. 144.

7 Ibid.

8 My discussion of “impersonal knowledge” is indebted to an unpublished paper of, and discussions with, Risto Hilpinen. My efforts, however, to shake Hilpinen's confidence in the possibility of impersonal knowledge have so far been unsuccessful.

9 Whether even the “normal” semantics of logical particles are not “irrelevantly abnormal” is a question seriously raised in recent work on relevance and significance logics. See esp., “The Pure Calculus of Entailment”, Belnap, N.D. and Anderson, A.R. Journal of Symbolic Logic,vol. 27 (1962)Google Scholar; and, more recently, Anderson and Belnap's Entailment, Martinus Nijhoff, 1974.

10 Philos. Studies, op. cit., p. 408.

11 In a much longer, but still uncompleted study of belief, I suggest the following principle for a rational epistemic agent: (Let ‘(n)’ mean “some degree of”) Ba(p v q) ⊃ (n) Bap & (n) Baq.

12 Ajatus, 32 (1970).

13 This is Hintikka's, but not Margolis', problem as Margolis doubts the possibility of a formal theory of knowledge being adequate.

14 The seminal treatment of this notion are to be found in “Knowledge and Reasons,” Williams, B.A.O. and “Comments on Professor Williams’ ‘Knowledge and Reasons,’” Ayer, A.J.; both included in Problems in the Theory of Knowledge,(ed.) Wright, G.H. von Martinus Nijhoff, 1972.Google Scholar