Showing posts with label deflationary theories of truth. Show all posts
Showing posts with label deflationary theories of truth. Show all posts

Monday, March 28, 2016

What I say

"What she said" in the vernacular is a way of expressing or agreeing with what the speaker just said. We can extend this useful idea in all kinds of ways. E.g.

(1) we can apply a negation operator. Thus 'not what she said'.

(2) we can apply it recursively. Thus

A: Snow is white
B:what A said
C:what B said

and so on. Note that all three are statements, each of them says something. Thus to say something is either (i) to say something without reference to another statement. This is the boundary condition. (ii) to reference some other statement which also says something. This is the recursive case.

(3) We can use other pronouns than the third person. E.g. to saying to C, 'not what you said', thus disagreeing with C, and thus disagreeing that snow is white. In the first person 'what I said', emphasising again what you said before, 'not what I said', changing your mind, as we do. And finally 'not what I am saying'. Does this say anything? No. It is a recursive case that has no boundary condition.

(4) Finally, we can ask a question. Thus 'what C says?', to which the answer could be 'what C says', or just 'Snow is white', or 'not what C says', thus 'Snow is not white'. As for 'not what I am saying?', there is no appropriate answer, given that 'not what I am saying' has no boundary condition, as in case (3) above.

Thursday, September 29, 2011

Objective reality revisited

The proprietor of Maverick Philosopher, who we will call 'Bill', has just posted about my comments on objective reality. Definitely worth reading, but makes me realise my comments (that there is such a thing as 'objective reality') were not entirely consistent with what I have been strenuously maintaining both here and over there,  namely that there is no such thing as objective reality after all.  For example, way back here, or here.

I have argued that there are no truthmakers, otherwise the truth of 'it will be sunny tomorrow' would depend on the existence of a present truthmaker.  But if that truthmaker does exist, then a few seconds later it did exist. But we can't change the past, so we can't change the truthmaker, and since the truthmaker makes the future true, it follows that we can't change the future.  But we can change the future: it is not determinate.  Therefore there are no truthmakers.  Therefore there is no 'objective reality'.

Fortunately Bill failed to spot this irregularity.

Thursday, April 07, 2011

Reference, truth and fiction

David Brightly perceptively writes
Can we take a closer look, then, at the Ockhamist theory of proper names? One implication appears to be that, for understanding and deciding the truth of a set of sentences, eg, the Dido and Aeneas story, we can do without the notion of reference altogether. The story can be thought of as a pattern or template or specification with blank spaces or empty slots. The pattern is to be offered up to the world and if we can find objects that fit the slots then the story is true. Names serve merely to label the slots and convey what relations between the slot occupiers are to hold. There is a strong whiff of circularity here which will need to be addressed. Basically, the pattern matching has to be done non-linguistically. But the upshot appears to be that the finding of the objects that satisfy the story is what makes them the referents of the names, under the usual understanding of 'reference'. So we had things backwards all along. This makes some sense to me but it doesn't seem to gel with your 'proper names are descriptive, signifying 'haecceity''. Could you expand on that?
First point: we aren’t doing without the notion of reference. As I pointed out here, we sometimes need to ask which fictional character is being referred to. A GCSE paper may ask which character is being referred to, and the answer might be

(*) Shakespeare is referring to Gertrude.

This means that ‘refers to’ is logically instransitive. We can refer to a dragon by name, and we can grasp which dragon is being referred to, even though nothing is a dragon.

It follows that the truth-conditions of sentences like ‘Shakespeare is referring to Gertrude’ involve nothing in the world, at least as far as ‘Gertrude’ is concerned. The ‘reference’ in question is not some mysterious semantic relation between Shakespeare and some mysterious, non-existing fictional object. There is no such object and no such relation. “Shakespeare is referring to Gertrude” clearly has truth-conditions, but these can only involve word-word relations, and possibly authorial intentions. More about that later.

David’s second point is more problematic. What determines the truth of a set of sentences, such as in the Dido and Aeneas story? According to classical logic, the sentence ‘Fa’ is true when the logically proper name ‘a’ individuates or identifies or locates or ‘refers’ to a really existing object, and when the predicate ‘F-' is satisfied by that object. It is this account that David is probably alluding to when he says “The pattern is to be offered up to the world and if we can find objects that fit the slots then the story is true”. It means we must countenance semantic relations between proper names and the world, and between predicates and the world. I have denied the existence of any such relations. Understanding the meaning of a sentence cannot be dependent on the existence of any objects except language and the mind. Meaning is object independent. But then how do we explain truth? More later.

Saturday, June 05, 2010

The Prosentential Theory of Truth

In a comment to Vallicella here I mentioned an article on the pro-sentential theory in the Internet Encyclopedia of Philosophy, and said that the theory has 'some affinity' with the 'assertoric' theory of truth I have sketched out here (as well as fiercely defended at Vallicella's place.

Here, I will take some of the claims made for the prosentential theory in that article and compare them with the corresponding claims of the assertoric theory, to see how close the affinity is.

The Assertoric Theory
The assertoric theory of truth is that the copula 'is' of a simple declarative subject-predicate sentence, such as

Tom is running

contains two components. One is the copula, whose function is to join subject and predicate to form the 'content' of the sentence. The content we can signify by a noun phrase such as 'that Tom is running' or the verbal noun 'Tom's running'. The other is the assertoric component, whose function is to signal assertion, i.e. to signal that the person uttering the sentence is saying something capable of being true or false. We can make the internal structure of such a declarative sentence transparent by parsing it as follows:

It is true / that Tom is running

The Prosentential Theory compared to the Assertoric Theory
1. "According to the prosentential theory of truth, whenever a referring expression (for example, a definite description or a quote-name) is joined to the truth predicate, the resulting statement contains no more content than the sentence(s) picked out by the referring expression."

Although the theories are similar, the fundamental difference is that, according to the assertoric theory, the 'truth predicate' (actually the truth operator) operates on a noun phrase signifying the content of the sentence, not the sentence.

2. "The central claim of the prosentential theory is that ‘x is true’ functions as a prosentence-forming operator rather than a property-ascribing locution."

The central claim of the assertoric theory is that 'x is true' functions as an operator on a 'that'-clause that forms a normal sentence (not a 'prosentence'). It claims also that this operator is implicit, though not lexically visible, in a sentence that does not use the words 'is true'.

3. "According to the prosentential theory, the statement ‘p is true’ says no more than the statement ‘p,’

The corresponding claim in the assertion theory is that 'it is true that p' says no more than that p. I.e. 'It is true that Tom runs' says that Tom runs. However, the theory distinguishes between the operator 'it is true that', which operates on a sentence to produce another sentence (of equivalent meaning), the operator 'that' which operates on sentences to produce a noun phrase, and the operator 'it is true' which operates on 'that' clauses to form sentences. This is a crucial feature of the theory which is necessary to prevent the 'substitution problem'. If we substitute the noun phrase 'that Tom runs' for 'p' in 3 above, we get the nonsensical

(*) The statement 'that Tom runs is true' says no more than the statement 'that Tom runs'

which is nonsensical because 'that Tom runs' is not a statement, but a noun phrase. If by contrast we substitute the sentence 'Tom runs', we get

(**) The statement 'Tom runs is true' says no more than the statement 'Tom runs'

which is nonsensical because 'Tom runs is true' is not a well-formed sentence (it would be well-formed if we read it as 'that Tom runs is true', i.e. read the sentence as a that-clause, but then we are not substituting the same thing salva significatione. (To be fair, the IEP article does note the problem of substitution, but does not sufficiently explain how the prosentential theory overcomes it).

4. " The prosentential theory of truth counts as a ‘deflationary’ theory because it denies that any analysis of truth of the form "(x)(x is true iff x is F)" can be given, where ‘x is F’ expresses a property that is conceptually or explanatorily more fundamental than ‘x is true.’ "

The assertoric theory is also a deflationary theory on this criterion. According to the assertoric theory, 'is true' operates on a noun phrase (a that-clause) to form a sentence. This operator is present, explicitly or implicitly, in the main verb of every declarative sentence. It is fundamental to the semantics of the declarative sentence, and no more fundamental explanation is available.

5. "The prosentential theory of truth implies a solution to the liar paradox. Consider the following sentence.- This sentence is false - if it says something true, it is false ... if it says something false ... it is true. [... ] Some attempts to solve the liar paradox involve extreme measures. Tarski, for example, thought that the paradox could be avoided only by eschewing ‘semantically closed languages’ [...] Tarski succeeds in avoiding the basic form of the liar paradox—but only at a very high price. He must content himself with providing an account of ‘true-in-Li’ rather than an account of truth. And, since natural languages like English are semantically closed, Tarski’s theory also has the weakness of applying only to artificial languages. ... According to the prosentential theory, (43) is neither true nor false because it fails to pick up an anaphoric antecedent. Just as I cannot inherit my own wealth, a prosentence cannot inherit its content from itself. "

The assertoric theory solves the Paradox in essentially the same way. 'is true' is fundamentally an operator, not a predicate. When attached to a 'that'-clause, it does not predicate anything or attribute anything to anything named by the clause. It merely signals that the speaker is asserting the content signified by the clause. In the case of the Liar sentence, there is no content to be asserted. According to the assertoric theory, we must analyse every declarative sentence into a content-part, and an assertoric part. Thus the Liar sentence must be analysed as

What this sentence says is false.

where the content part is signified by 'What this sentence says', and the assertoric part to the denial 'is false'. But the sentence says nothing, because the attempt to locate a referent for it fails.

Friday, June 04, 2010

Deflationary theories of Truth

A common objection to deflationary theories of truth is sentences like 'Everything Tom says is true'. Analysing this as

(A) For all p, if he asserts p, then p.

results in incoherence when we attempt to substitute. If we substitute sentences like 'snow is white', we get

(B) If he asserts 'snow is white', then 'snow is white'.

which is nonsense. If we substitute propositional content, signified by a 'that' clause, we get

(C) If he asserts that snow is white, then that snow is white.

which is also nonsense. However, we can evade this difficulty along the lines I have suggested in earlier posts. The first insight is that 'it is true that' is a complex operator built from 'it is true', which operates on 'that' clauses to form declarative sentences, and 'that' which operates on sentences to form 'that' clauses. Then it is coherent to hold that the semantics of any declarative sentence can be represented formally as

(D) |- c

where the operator |- corresponds to the 'it is true' part, and 'c' to a that-clause. I.e. we parse 'it is true that Tom runs' as 'it is true / that Tom runs'. Then the problem sentence 'He is always right' can be analysed as

(E) If he says c, |- c

Suppose for example that he says that Tom runs. then c = that Tom runs (note I substitute a 'that' clause, not a sentence), and |- = 'it is true', as above. This yields

(F) If he says that Tom runs, it is true that Tom runs = if he says that Tom runs, Tom runs

which makes perfect sense.