Incorporating doxastic-boulemaic operators to System GHP

By J. L. Speranza
for the Grice Club

I am exploring some bits of "it is believed", as mentioned by Grice in "Vacuous Names" as needed for an 'interesting', he calls it, 'weak notion of identity', that yields Pegasus as identical with Pegasus but not with Bellerophon.

I have explored this elsewhere, and I have to thank J for providing input for further explorations.

I will refer in passing to J's important points -- notably in his comment to blog post, "Pegasus not identical with Bellerophon".

As it happens, Grice's 'Vacuous Names' ends with a note on psychological properties. His example concerns

"Martha"

John desires to marry Martha. Martha, of course, does not exist. John was led to believe that Martha is his friend Charles's delectable sister, whereas in fact Charles is an only child.

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Grice's natural deduction system copes well with that, and it would not have surprised Quine (for whom the system is offered) since it's all about the opaque reading versus the tranparent readings of such verbs as 'believes' and 'desires' as we quantify in or out. Grice does not consider the case with definite descriptions, and his 'stroke-of-the-pen' move, "Let's call him Bill".

Thus, one can say that a female wants to marry the chief executive of Gates Company -- let's cal him Bill.

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Back to "Pegasus".

I have NOT studied that myth, and would not know how to provide a lot of 'believes that' to do the duty, but I would think that, for one, Pegasus was believed to be a horse, whereas Bellerophon was believed to be a human, so that's not identical enough.

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J notes that 'belief' is possibly too folksy for anything serious and relies on Patricia (and her husband) Churchland.

In fact, part of the fashion for the Churchlands arose from the interest given by analytic philosophers, such as Grice, to such issues.

In 1975 Grice delivered "Method in philosophical psychology: from the banal to the bizarre" (American Philosophical Association, Pacific Division, San Diego -- Presidential address) so the Churchlands should have been aware of that. Especially since Grice cares to take good care of the account only THEN starting to be popular after attempts by D. K. Lewis, of revamping some sort of Aristotelian functionalism.

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That essay has been blissfully reprinted by J. Baker in Grice's "Conception of Value" and I often think that it is THAT reprint that makes for an excellent volume. I mean, the Carus Lectures (The conception of value) are sublime, but technical. Wherewas "Method in philosophical psychology" is BASIC philosophy of mind --. If we could have the same sort of clear manifesto for all the other philosophers of Austin's playgroup I should be damned! (Try to locate the philosophy of mind of P. F. Strawson, or R. M. Hare, or S. N. Hampshire, or G. J. Warnock, or even J. L. Austin, or D. F. Pears, ...).

Grice is clear as to what he means. He is NOT a Rylean. He does NOT want '... believes ...' to be reduced to 'behaviour'. He wants '... believes...' to stand for a theoretical term. In this, his approach very much resembles Carnap's cursory treatment of belief and assertion as the main concepts of pragmatics. Carnap, too, saw belief as a theoretical construct. There are more analogies with the Carnap view, too, and I was saddened to see that Carnap could never have read Grice's paper since this was in 1975, and Carnap was dead by then --.

For example, Grice dwells extensively on the Ramsey theoretical-observation correspondence rules that had been brought to the fore on the issues of philosophical psychology by Carnap himself -- and in fact, the project of establishing some sort of psychology on a 'systematic account' of some sort rang a bell with early verificationist and positivist approaches.

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So I would think that Grice saw that it would not be incoherent to state, "This Greek thought that Pegasus was a horse with wings -- that he used to fly".

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Matter of fact, Grice goes further -- he wants to reduce 'belief' to 'desire' and he succeeds! What I mean by this is that he saw the depth of a psychological operator as being unique. Once you get a grip of the logical form of a psychological attitude ascription, it won't matter much whether it is 'belief' or 'desire' and one can be defined in terms of the other. He suggests that desire can thus similarly be defined in terms of belief but does not suggest the how.

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The way to go with the system GHP is then to use some of the symbolism in Grice's "Studies in the Way of Words". He uses

psi

as a predicate for any psychological predicate.

He wants to talk of

A holding predicate psi concerning content 'that p' as a way of saying that "A accepts that p".

To accept, in Grice's jargon, is either to believe or to desire.

There are laws o 'acceptance' that are independent of its modus -- you accept that the sky is blue and you accept that eating people is wrong.

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The operators of a logical nature (conjunction, disjunction, if-clauses) similarly should be introduced independently of the modus of the attitude.

If Peter believes that St. Paul's is in Rome and believes that the Pope lives in St. Paul's, he believes the Pope lives in Rome.

--- If A desires to go to St. Tropez and believes that if he goes there he'll meet Brigitte Bardot, he ... -- whatever.

Belief and desire interact, and it would be otiose if one would need to introduce the logical constants for each modality --.

Consider 'reason'. To reason, is, after all, a matter of 'acceptance'. The magic of a practical syllogism is that it has a premise which concerns a belief (about the means) and a major premise which concerns a desire about the goal. The conclusion is a desire about the adoption of the means. And so on.

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Grice would think that, yes, it may all be folksy, -- so? As Louis Armstrong said of the similar folk songs -- Yes, I never heard a horse sing one. Or something!