benardete on sense perception and the a priori

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Mind Association Benardete on Sense Perception and the a Priori Author(s): M. Mullick Source: Mind, New Series, Vol. 81, No. 322 (Apr., 1972), pp. 280-283 Published by: Oxford University Press on behalf of the Mind Association Stable URL: http://www.jstor.org/stable/2252632 . Accessed: 24/06/2014 22:52 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. . Oxford University Press and Mind Association are collaborating with JSTOR to digitize, preserve and extend access to Mind. http://www.jstor.org This content downloaded from 185.2.32.58 on Tue, 24 Jun 2014 22:52:31 PM All use subject to JSTOR Terms and Conditions

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Page 1: Benardete on Sense Perception and the a Priori

Mind Association

Benardete on Sense Perception and the a PrioriAuthor(s): M. MullickSource: Mind, New Series, Vol. 81, No. 322 (Apr., 1972), pp. 280-283Published by: Oxford University Press on behalf of the Mind AssociationStable URL: http://www.jstor.org/stable/2252632 .

Accessed: 24/06/2014 22:52

Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at .http://www.jstor.org/page/info/about/policies/terms.jsp

.JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact [email protected].

.

Oxford University Press and Mind Association are collaborating with JSTOR to digitize, preserve and extendaccess to Mind.

http://www.jstor.org

This content downloaded from 185.2.32.58 on Tue, 24 Jun 2014 22:52:31 PMAll use subject to JSTOR Terms and Conditions

Page 2: Benardete on Sense Perception and the a Priori

BENARDETE ON SENSE PERCEPTION AND THE A PRIORI

IN a recent article in Mind (April 1969), " Sense Perception and the a Priori " Mr. Benardete has claimed that contrary to the widely accepted doctrine of the distinction between the a priori necessary and the a posteriori contingent, there can be and is, both empirical knowledge of the necessary and a priori knowledge of the world.

In what follows I wish to examine this claim by analysing some of the major arguments on which it rests. The outcome will be, not a reiteration of the old fashioned defence of a dogma, but one based on a reappraisal of the necessity concept. Indeed the view of necessity advocated here will find the originators and upholders of the analytic-synthetic distinction as unsympathetic as they will be towards Benardete's arguments, which it attacks.

The term ' necessary ' is nowhere defined by Benardete in his article, but an analytic proposition he tells us " is here understood to be a necessary proposition the denial of which is self contra- dictory ". 1 Since it is not likely that Benardete recognises a class of necessary propositions the denials of which are not self-contra- dictory, we may take it that he employs the terms ' analytic ' and ' necessary' as synonymous. Later we get another statement con- cerning the analytic which Benardete hopes to refute:

" A proposition is analytic if it is true solely in virtue of the meaning of its constituent symbols and cannot therefore be either confirmed or refuted by any fact of experience." 2

Benardete's first argument to show that a necessary proposition can be verified through sense perception is that the proposition "there are lions or there are no lions " is immediately derivable from "there are lions ", which is known (after all) through sense experience. Now, indirectly it is true that any proposition that is logically derivable from an empirically verified proposition is itself verified. But its verification in such cases is at best only partially empirical since it requires the further aid of a law of logic-in this case the prin- ciple of Addition-to show how it is related to the directly verified proposition. Further, the proposition " there are lions or there are no lions " is related to the proposition " there are no lions " in exactly the same way as to " there are lions ", but the former happens to be an empirically false proposition. In this case we obviously do not wish to say that the necessary proposition is verified. This, because verification can result only on the basis of true empirical propositions which imply the proposition in question. But then in both truth-functional and modal logic the proposition " there are lions or there are no lions " since it follows from any proposition, follows from any true empirical proposition whatever.

1 Sense Perception and the A Priori. 2 op. cit. p. 162. Note that if the word ' further' is inserted immediately

before 'confirm' this would immediately draw the sting out of any claim that it can be so confirmed. For can one further confirm that about which there is no doubt?

280

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Do all such propositions serve to ' verify' the necessary proposition? By the 'parity of reasoning' that Benardete himself invokes, on his account they do!

One begins now to see that there is a trick in the argument, though it has nothing to do with the Rule of Addition.' It has rather to do with the (mis)use of the verb 'to verify' in a context where its con- trary 'to falsify' has no possible application, thereby rendering " to verify" itself insignificant, not to say meaningless, but without admitting as much.

The next argument that Benardete offers goes to show that when there is a logically false conjunction, its negation may be known to be true by some individual purely because he knows that one of the conjuncts is in fact false. Now as a matter of pure experience, this is of course possible. But at this point Benardete's argument begins to falter. He claims in connection with the example described, " One man knows that the proposition is true on a priori grounds, the other man knows it to be true on a posteriori grounds. It is one and the same proposition which is known to be true by the two men" (op. cit. p. 162.)

But is it? What A knows on a posteriori grounds is that the conjunction is not true. But what B knows on a priori grounds is that the conjunction cannot be true. It is the limitation of truth- functional logic (or merely irrelevant for its purposes) that this distinction cannot be expressed within the language without the use of the metalinguistic symbol' F '. Nevertheless, what logic estab- lishes is ' F , (p. p) ' and not merely ' - (p. - p) ' and these two expressions are not identical: not as physical sequences, and cer- tainly not as intensions or propositions.

To give a particular source of knowledge is also to limit or deter- mine the sort of thing one can thus know. The fact is of course, that the knowing process is a fairly mixed up affair: we seldom acquire knowledge only through one kind of source. There is how- ever no call to mix up the concepts of knowing through sense per- ception and knowing a priori. To know a proposition a priori without assuming an empirically known premise is to know that given our conceptual scheme, it is necessarily true. Such a propo- sition cannot be identical with that which is verified directly or indirectly with the aid of sense experience.

Benardete's own argument supports this conclusion. Looking at an entire truth table (he says), we are able to verify the tautology- hood of a symbolic expression. But given any one set of truth conditions as the one that actually obtains, we can also verify the truth of the expression. This latter method of verification is empirical and Benardete admits that " though sense perception has enabled us to verify the proposition, it has not afforded us any grounds

1 Op. cit. p. 162. Here Benardete says, " In suspecting a trick in my argu- ments one may be led to suppose that it is the Rule of Addition which is being put to some mischievous use."

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Page 4: Benardete on Sense Perception and the a Priori

282 M. MULLICK:

for concluding that the proposition is logically necessary ". That however, he says, is " another matter entirely. Although we have in fact verified a necessary proposition we do not know that we have done so " (op. cit. p. 164).

Benardete's case now rests on this last statement, and in examining it we have to ask: Is it possible to have verified a necessary propo- sition without knowing that one did so? I have argued elsewhere' that necessity is a relation between propositions not a property of them. To put it another wav it is logically a two-place, and not a one place predicate. What this means is that after knowing that a necessary relation exists between two relata, there is no further fact that the proposition stating this is necessary, and which one may or may not be aware of. If this is so, then to verify a so-called necessary proposition is to come to know that a necessary relation exists. And to know that a necessary relation exists, is in one widely accepted sense of 'necessary ' to know that it holds for all possible worlds.

We have been warned against the bewitchment of language. But let us be wary of the bewitchment of symbols too. Because in the symbolism of modal logic the modal operator falls outside the sym- bolic expression one is apt to conclude that it attaches externally to the entire expression. Not so. The status and interpretation of the connectives is itself changed by the presence of the modal operator.2 Necessity is thus a built-in concept. This answers Benardete's statement that " though analytic propositions do hold for all possible worlds, they do not characteristically assert that they do ".

Now it is perhaps true that we do not characteristically use modal terms in asserting necessary propositions unless we are pressed to in argument. But the logical analysis of necessary truths cannot vary with the idiosyncracies of speech. Mathematical propositions are most often stated without the use of ' necessarily' or 'must' and other modal terms. But that is only because there is an understand- ing among those who speak the language that within this particular universe of discourse all propositions are understood as asserting necessary relations. (Of course this view of mathematics can, and has been challenged, but not by Benardete.) If this is correct then Benardete's entire discussion regarding the identity of Goldbach's theorem and a proposition of the same form but empirically verified, is taken care of, and the essential wisdom of Hume vindicated. In a universe of exactly one hundred individuals it is possible to verify that in fact every even numbered collection consists of two collections whose cardinal number is prime. Would we, in verifying this have proved Goldbach's theorem? No, because the theorem would be a

1 ' Necessity and Entailment' in the forthcoming issue of the Journal of the Indian Philosophical Association.

2 The modal operator is immediately succeeded by the connectives. Thus in the expression LNKpNp ' LNK ' may be viewed as a composite modal operator which has for its arguments p and Np.

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Page 5: Benardete on Sense Perception and the a Priori

SENSE PERCEPTION AND THE A PRIORI 283

proof that every even numbered collection must be the sum of two prime numbered ones, otherwise it would not be what we commonly understand by 'a theorem'. Thus the two propositions will not turn out to be informationally identical as Benardete claims even if Goldbach's theorem is proved true. Nor will we ever suddenly discover either that the empirically verified proposition (E) is merely contingent the day Goldbach's theorem (M) is proved false or that it is " without sense " if Goldbach's theorem is proved true. (M) is not (E) plts the modal operator (op. cit. p. 169). By attempting a parody of Wittgenstein's position Benardete reveals what is essentially signi- ficant in it. Wittgenstein's whole argument is that tautologies say nothing significant about the world (though they do about our con- ceptual scheme). What so desperately needs recognition here is the difference between two languages whichtogether make up the language which we speak: one with a vocabularylimited to talk of the world, the other, to talk of logic. The fact that some physical sequences occur in both does not prove that the propositions they contain are identi- cal; at least no more than the fact that the same sound is used to denote water in one language and bread in another proves that it is one and the same word in both.

Time and again Benardete seems to show glimmerings of this same insight, as when he says, " Our assertion of an empirical con- nection ... remains a factual assertion " though he adds " even if that assertion should be logically necessary "(op. cit. p. 170). So now we are being asked to admit that we can make assertions with- out knowing what we assert.

There are a number of notions that Benardete introduces in the course of attempting to establish his thesis, that I find controversial; 'criteriologically analytic ' ' semantically analytic' as opposed to (?) ' logically analytic ', ' epistemically analytic '; and so on. But I am concerned at the moment to make just one further point.

Benardete concedes that there is some difference between propo- sitions such as (1) " Either it is raining or it is not raining " and (2) " Either it is raining or there are lions ". The former he admits is in some sense 'radically uninformative' while the latter is not. This uninformativeness does not follow however from its necessary nature because we would not wish to label as uninformative the propositions of mathematics. Still, we do find the proposition (1) " Either it is raining or it is not raining " uninformative because " we find it difficult-it may even be impossible to imagine circumstances in which someone hitherto ignorant of (1) comes to learn of its truth." " We cannot envisage anyone's being informed of anything, through (1)" (ibid. p. 166). After this admission, can Benardete still persist without contradicting himself in the claim, that it is possible to empirically verify (1) from the circumstances that it is raining? And is to verify a proposition anything else than " coming to learn of its truth " on the basis of some good evidence?

I.I.T. Kanpur M. MULLICK

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