Tuesday, 11 January 2011

Wright's Private Language Argument Refuted

(currently unpublished) copyright to myself. Feel free to link but do not repost.

ABSTRACT: Wright’s Private Language Argument Refuted

Crispin Wright has developed a novel take on the private language argument presented by Wittgenstein in Philosophical Investigations PI 258-60. Wright’s private language argument is ingenious and important, and it has not, to date, been refuted. In this paper I refute Wright’s argument, pointing out that it commits the fallacy of equivocation (it trades on an ambiguity in his use of the phrase “reason to believe”). While there may be a cogent private language argument presented in PI 258-60, Wright has failed to hit upon it.



Wright’s Private Language Argument Refuted

Introduction

Suppose our sensations are necessarily private and inaccessible to others. That would seem to introduce the possibility of a subject introducing a private sensation-language the meaning of which would necessarily be unknown to others. Suppose, for example, that I define “S” by reference to my private sensation. I focus my attention on the inner phenomenon, thereby impressing on myself the connection between sign and sensation. I might then use “S” to record facts about my private mental life. For example, I could use it to record in my diary those days on which I have that particular sensation. The meaning of “S” would necessarily be unknown, and necessarily unteachable, to others.

In Philosophical Investigations (PI) §§258-60, Wittgenstein appears to present an argument against the possibility of someone introducing such a “private language”. However, it remains controversial both what the private language argument is, and whether or not it is cogent.

In Does Philosophical Investigations §§258-60 Suggest A Cogent Argument Against Private Language? Crispin Wright presents an argument suggested to him by §§258-60, an argument that Wright believes is, in fact, cogent. That argument has not, as yet, been refuted. I aim to refute it here.

Wright’s private language argument

Wright begins by making a case for two key principles. The first principle lays down a condition on a sentence being apt for the expression of a fact. According to Wright,
sentences of a given family are apt for the expression of a fact only if:

(a) X believes what “P” expresses,

and

(b) What “P” expresses is true.

have an appropriately contrasting content where “P” is any of (appropriately many of) the sentences in question. (1986:228)

Wright’s second principle is that (a) and (b) will have appropriately contrasting content only if:

the information conveyed by (a) should differ from that conveyed by (b). And it is plausible that, for a large class of examples, two items of information differ just in case there can be such a thing as reasonably regarding oneself as possessing one and not the other. (1986:230)

These two principles have some prima facie plausibility, and I shall, for the sake of argument, concede both here. Wright then proceeds as follows. From the second of the above principles, Wright derives the interim conclusion that

we are entitled to regard (a) and (b) as conveying different items of information only if someone could have reason to believe one but not the other and could be aware of the fact. (1986:231)

The final step in of Wright’s argument is to show that, where “P” is a sentence of a putative private language (such as, “I am having S again”), it is not possible that someone could have reason to believe (a) but not (b), or vice verse. Wright continues:

The argument will be that when “P” is, putatively, a sentence of a language which no two people could reasonably believe they share, that is not a possibility.

It will suffice to consider four cases. Letting “A” range over believing subjects, we have

(i) A is aware of possessing both reason to believe (a) and reason to doubt (b);
(ii) A is aware of possessing both reason to doubt (a) and reason to believe (b);
(iii) A is aware of possessing both reason to believe (a) and no reason to believe (b)
(iv) A is aware of possessing no reason to believe (a) and reason to believe (b).
(1986:231)

Wright believes that, whether A is X him- or herself or some third party Y, if “P” a sentence of a private language, none of the above four cases can obtain. It thus follows, according to Wright, that “P” cannot state fact. A language in which one might state facts concerning one’s own private sensations is impossible.
Wright deals with cases (i) to (iv) in turn, in each case providing one or more arguments for why, if “P” is a sentence of a private language, that case cannot obtain. I shall not run though all these arguments. It will be instructive, however, to run through Wright’s argument that, where “P” is a sentence of a private language, (iii) cannot obtain.

Let’s begin by supposing that A is not the putative private linguist but a third person Y. Wright’s argument that Y cannot be aware of possessing both reason to believe (a) and no reason to believe (b) is as follows.

True, Y does not know which aspect of X’s psychological state “P” concerns. However, Y does know that “P”, as used by X, concerns some aspect or other of X’s psychological state. And it is, generally, a feature of psychological states that the subject of such a state be some sort of authority about it. So if, for example, Y has reason to suppose X believes he is experiencing S again, then Y also possesses some reason to believe X is experiencing S again. As Wright puts it:

[I]f one may at least suppose that “P”, as used by X, concerns some aspect or other of X’s psychological state, then one is bound to take reason for (a) as supporting (b); and note that the point is not dependent on crediting X with Cartesian authority for his psychological states – it is enough that he be any sort of (fallible) authority about them, that his opinions about them count for something. (232)

Wright concludes that, where “P” is a sentence of X’s putative private language, Y cannot be in state (iii).

What if A is X – the putative private linguist him or herself? Can A then be in state (iii)? No, says Wright. X’s belief that “P” is true gives X grounds for believing “P” is true, for, again, “P” concerns X’s own psychological state, something about which X must surely be considered some sort of authority.

Refutation of Wright’s private language argument


Wright’s argument is not cogent. As indicated above, Wright begins by appealing to the principle that
two items of information differ just in case there can be such a thing as reasonably regarding oneself as possessing one and not the other. (1986:230)

But notice that this principle allows (a) and (b) to convey different pieces of information even if it is true that possessing reason to believe one immediately provides one with some reason to believe the other. For the situation may be that, while the existence of reason to believe (a) inevitably provides one with some reason to believe (b), the degree of support provided to each belief may differ, raising the possibility of it being reasonable to regard oneself as possessing one piece of information but not the other.

Here’s an analogous case. Consider the two pieces of information: Fred is a Christian, and: Fred is religious. Ceteris paribus, evidence supporting one of these beliefs inevitably provides at least some support the other. Yet it is entirely possible reasonably to regard oneself as possessing the latter piece of information but not the former.

To show that the information conveyed by (a) and (b) does not differ, Wright must show that it is impossible for one reasonably to regard oneself as possessing one piece of information but not the other. Wright fails to do this. He points out, no doubt correctly, that if, for example, A has reason to believe (a), then, because “P” concerns the putative private linguist’s own psychological state (something about which the private linguist must be considered some sort of authority), A will also have some reason to believe (b). But note that this fact is entirely consistent with it being reasonable for A to regard him or herself as possessing the information conveyed by (a) but not the information conveyed by (b). Thus it is also consistent with (a) and (b) conveying different pieces of information.

For example, suppose Y knows both that X defined “S” by reference to one of X’s psychological states and also that X has not given any thought to his definition until months later, when X is suddenly convinced he is experiencing S again. This delay may makes it rational for Y to entertain serious doubts about the reliability of X’s memory concerning how “S” is should be applied. In these circumstances, Y’s knowledge that X believes that he is experiencing S may give Y some reason to suppose that X is experiencing S again, as Wright maintains. But of course it may not be reason sufficient to make it reasonable for Y to regard him or herself as possessing the information that X is experiencing S again. Thus Y may reasonably regard him or herself as possessing the information that X believes he is experiencing S again, but not the information that X is experiencing S again. In which case, if sentence “P” is “I am experiencing S again” (as uttered by X), Wright has failed to give us any reason why the information conveyed by (a) and (b) cannot differ.

The fallacy of equivocation

Let me identify precisely where Wright’s private language argument goes wrong. It commits the fallacy of equivocation. Wright argues from the principle that

two items of information differ just in case there can be such a thing as reasonably regarding oneself as possessing one and not the other. (1986:230)

to the interim conclusion that

we are entitled to regard (a) and (b) as conveying different items of information only if someone could have reason to believe [my italics] one but not the other and could be aware of the fact (1986:231).

But what does “reason to believe” mean in the interim conclusion? The phrase “reason to believe” is ambiguous. It might mean, for example reason sufficient to make it reasonable to believe, or it might just mean some (possibly inadequate) reason to believe.

Now notice that Wright’s interim conclusion follows from his principle only if “reason to believe” means the former, not the latter. For we might still reasonably regard ourselves as possessing one item of information but not another despite that fact that possessing reason to believe one thing inevitably gives us some reason to believe the other.

Wright then claims that, where “P” is a sentence of a putative private language, the impossibility of cases (i) to (iv) suffices to show that (a) and (b) must convey the same information.

But notice that in cases (i) to (iv) “reason to believe” presumably means only some (possibly inadequate) reason to believe. Otherwise, for example, Wright’s case (iii):

A is aware of possessing both reason to believe (a) and no reason to believe (b)

comes out as the case in which A is aware of possessing both reason sufficient to make it reasonable for them to believe (a), but not reason sufficient to make it reasonable for them to believe (b) – a case which, as we have seen, is possible, i.e. because, while having reason to believe (a) immediately gives A some reason to believe (b), the reason A possesses for believing (a) may be much stronger than for believing (b), thereby making it reasonable for them to believe (a) but not (b).

In short, Wright’s private language argument trades on an ambiguity in the use of “reason to believe” - on an unwitting slide from one way of using that phrase to another. It commits the fallacy of equivocation.

There may be a cogent private language argument contained in PI 258-60. What is now clear. I believe, is that Wright has failed to hit upon it.

3 comments:

Daniel Fruhman said...

Isn't the correct interpretation of Wittgenstein's argument that S couldn't exist in the first place. S would be meaningless the first time it was ever uttered by X and therefore your example about Y placing doubt on X's memory is unnecessary. Y should doubt when X says I am experiencing S in the first place because S is meaningless.

Daniel Fruhman said...

Isn't Wittgenstein's private langauge argument meant to show that S is meaningless in the first place. So Y should doubt that X has ever expressed anything meaningful the first time he ever said 'S.' So perhaps Y can believe that X believes that S is occurring because X thinks he can use S meaningfully, but he should always doubt that S is occurring (not because of X's memory) but because S is inherently meaningless because its a term denoting a private sensation.

Philip Rand said...

This was an interesting paper Dr Law.

How about this case:

A new born human child minutes out of its mother's womb is brought to its mother's breast to feed.

The infant latches onto it's mother's breast and feeds.

Wouldn't Wright’s argument that the infant cannot be aware of possessing both reason to believe in the existence of the breast (a) and no reason to believe in the non-existence of the breast (b)

be valid?