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Saul Kripke, Wittgenstein on Rules and Private Language

Jonathan Abdalla

Even a casual reader of Saul Kripke’s monograph on the later Wittgenstein will

recognize immediately the vast amount of sustained engagement with Wittgenstein’s

texts on the part of Kripke. In addition to forceful analysis of Wittgenstein’s principal

theses, Kripke gives the reader a synopsis of the structure of the Philosophical

Investigations and an explicit reconstruction of the so-called “private language”

argument. For those more historically minded, Kripke addresses at least somewhat the

relations between Wittgenstein’s work and the work of Quine and Goodman among

others. Quite admirably, Kripke stays true to his title and concentrates on those

portions of the Philosophical Investigations that are relevant to his thesis; he also

covers certain parts of the Remarks on the Foundation of Mathematics.

The central thesis of Kripke’s monograph is that Wittgenstein in his later

philosophy of language recognizes a powerful skeptical argument against the coherence

of the notion of meaning and consequently offers a solution to it consonant with his

dictum that meaning is use. The two areas in which such a skeptical thesis seems most

damaging are mathematics and inner experience. Kripke sees the formative statement

of the paradox in §201 of the Philosophical Investigations: “no course of action could be

determined by a rule, because every course of action can be made out to accord with the

rule.” To make the claim as clear as possible, he begins with a mathematical example;

the case of inner experience would proceed analogously.

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It seems quite commonsensical that in grasping the rule of addition one has

determined one’s answer for any novel future sum. The skeptic, as all good skeptics do,

questions the certainty implicit in the claim of a rule being grasped. Let us say that

Bertrand has grasped the rule of addition. When pressed by the skeptic as to his

certainty in saying that the sum of 68 and 57 is 125, Bertrand replies that he is following

the rule for addition that he has previously grasped. The skeptic responds by defining

the function ‘quus’ as follows:

x ⊕ y = x + y, if x, y < 57;

= 5, otherwise.

He then asks how it is that Bertrand knows that in the past he has not always meant

‘quus’ by ‘plus’ and consequently should answer 5 instead of 125. This point is crucial.

The skeptic is not asking how Bertrand knows that 68 + 57 is 125, but rather how

Bertrand knows that 68 +57 should denote 125 as a consequence of Bertrand’s meaning

‘plus’ in the past. If Bertrand’s past usage of ‘plus’ denoted ‘quus’, then Bertrand’s past

intention was such that he ought to compute the sum as 5 rather than as 125.

Now, if Bertrand attempts to give an account of the facts about his mental states

that constitute his meaning ‘plus’, not ‘quus’, he seems to find himself in a dilemma.

The skeptic claims that there exist no facts about Bertrand’s past mental history, even

Bertrand’s past observable behavior, that establish Bertrand meant ‘plus’ rather than

‘quus’.

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Thus, the skeptical paradox is not epistemological; even an omniscient observer

would not know which of the two Bertrand meant. Furthermore, argues the skeptic, if

there exist no facts about which function Bertrand meant then, then there existed no

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Kripke acknowledges the close similarities between this skeptical argument and Quine’s thesis of the

indeterminacy of translation. He points out though that Wittgenstein’s allowance of introspective
evidence distinguishes him from Quine and his behavioristic limitations.

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facts then about which function Bertrand presently meant. If there exist no facts about

which function Bertrand presently meant in the past, then there exist no facts about

which function Bertrand means in the present. Hence, there exist no facts about what

one means by any word at any time. For Kripke, this is Wittgenstein’s skeptical

paradox.

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More systematically, the paradox rejects the notion of meaning as truth

conditions. The skeptic concludes that there exist no facts corresponding to sentences

such as “Bertrand meant addition by ‘plus’.” Consequently, any assertion involving a

meaning claim is meaningless.

Having dismissed a number of objections on behalf of Wittgenstein or on behalf

of himself, Kripke turns to the solution that Wittgenstein offers. Wittgenstein accepts

the skeptic’s rejection of meaning as truth conditions; this amounts to rejecting the

views of both Frege and the Tractatus. In its place, he offers a two-faceted theory of

language. In a move reminiscent of the positivists’ emphasis on provability conditions

in their verificationist theory of meaning, Wittgenstein partially characterizes meaning

in terms of assertability conditions. He completes this characterization by incorporating

the notion of the practical utility of such assertions. In application to the mathematics

example above, Kripke explains it this way: “Do not look for ‘entities’ and ‘facts’

corresponding to numerical assertions, but look at the circumstances under which

utterances involving numerals are made, and the utility of making them under these

circumstances” (77). This postulation of a new conception of meaning allows

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Footnote 43 on page 58 is fascinating. Kripke intimates that his idea of ‘quus’ quite possibly might have

arisen from reading Goodman on ‘grue’. In fact, if one considers not a mathematics problem but the
language of color impressions, it seems that ‘grue’ would play the role that ‘quus’ now plays. Of course,
the problem would not be Goodman’s new riddle of induction, but rather if one knows whether one ought
to call the sky green given that in the past one might have meant ‘grue’ by ‘green’.

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Wittgenstein to accept the skeptical premise without being forced to accept that all

meaning assertions are therefore meaningless.

Kripke roughly characterizes the assertion conditions for a sentence such as

“Bertrand means addition by ‘plus’” as follows:

[Bertrand] is entitled, subject to correction by others, provisionally to
say, “I mean addition by ‘plus’,” whenever he has the feeling of
confidence – “now I can go on!” – that he can give ‘correct’ responses
in new cases; and he is entitled, again provisionally and subject to
correction by others, to judge a new response to be ‘correct’ simply

because it is the response he is inclined to give.

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If Bertrand claims to be following a rule, then the community can check his claim.

Others in the community can see whether Bertrand as a putative rule follower is or is

not giving responses that agree with the ones that they themselves endorse. If they

perceive such agreement, then they judge that Bertrand has grasped the rule. Now, if

Bertrand were ever to begin to deviate substantially from how the community behaved,

then the community would conclude that Bertrand no longer grasped the rule.

Kripke is thus claiming that Wittgenstein offers a social theory of meaning. That

theory claims that there does exist a useful role in the life of the community for a

language game that allows people to assert meaning claims. Furthermore, within that

language game, one is allowed to assert that one’s present usage of a given word does

agree with how one used it in the past. It is here that the so-called “private language”

argument becomes relevant. Many think incorrectly that a private language is a

language that is impossible for anyone else besides its bearer to understand. Kripke

claims instead that by it Wittgenstein means that there can be no private way in which

to follow a rule. If one were to follow a rule privately, then one would be proceeding

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Kripke, 90.

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randomly or blindly, since there is no fact of the matter as to whether one rule or

another applies. One’s authority would be unconditional, and no one could say that any

behavior was correct or incorrect. However, when one steps up to the level of the

community, others then have the authority to assess that behavior as correct or

incorrect. As such, a private language is incoherent, properly understood.

Now, even given a social theory of meaning, it seems that membership in a

community is irrelevant to one’s characterization of one’s inner experience. As noted

before, Kripke sees Wittgenstein’s approach here as analogous to the mathematics case.

Here, instead of grasping a rule for addition, one would grasp a name for a sensation.

But, that naming is clearly conventional. Any normative force regarding the

conceptualization of a particular sensation and its continued usage arises from the

community. The community observes the behavior of a putative member together with

attendant circumstances and judges whether that person is using the word pertaining to

that sensation and state of affairs properly. For the record, Kripke also takes

Wittgenstein to have viewed the philosophical problem of the existence of other minds

as a narrow case quite close to the issues already addressed and to have constructed an

analogous skeptical problem and an analogous solution.

Interestingly, the centrality of the notion of community in Wittgenstein’s social

theory of meaning bears a striking resemblance to the work of Goodman and of Putnam.

Specifically, it seems that Wittgenstein would agree with Putnam that meanings are not

in the head. Where Putnam differs is in the complexity of the causal-historical theory of

reference that he gives to characterize meaning. Of course, both of these are positive

improvements over Quine’s rejection of meaning.

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In summary, let me say that Kripke’s monograph is an impressive model of

careful philosophical argumentation. Though he declaims it at times, it is clear that

Kripke is both offering an interpretation of Wittgenstein and asserting that Wittgenstein

does hold certain claims as true. Thus, it is legitimate to ask whether Kripke’s

interpretation is a plausible one. My suspicion from the portions of the Philosophical

Investigations that I have read is that Kripke’s reconstruction is just that. More

specifically, it is a reconstruction of what might be an argument in Wittgenstein and a

recasting of it in strict analytic terms. In other words, it seems to me that Kripke has

successfully rehabilitated the later Wittgenstein into the ranks of analytic philosophers.

But, that seems to be in great tension with the persona and attitude that Wittgenstein

portrays in the Philosophical Investigations. To say it another way, if Kripke’s reading

of Wittgenstein is correct, then I now understand what Wittgenstein was attempting to

accomplish in the Philosophical Investigations. My reading of Wittgenstein’s text does

not convince me in the least that I understand all of Wittgenstein’s thought. As such, it

seems the Kripke’s Wittgenstein is not the Wittgenstein of the Philosophical

Investigations. Nevertheless, I must say again that Kripke’s accomplishment is very

commendable. He has fashioned from a difficult text a quite plausible theory and

argued vigorously for it. I would that all interpretive work in philosophy met that same

standard.