Farewell to Semantics (part two)

So when are words replaceable in sentences starting with "I believe"?

Not when they denote the same thing, as shown by many examples of the "Morning Star/Evening Star" type. Not even when they have the same meaning, because the speaker (believer) many not know that they have the same meaning.

I suggest that replaceablity of words in intensional contexts must always taken relative to the subject of the sentence (= believer). The relevant relation would look more less like this"

(1) aD(B)a = a has for B the same denotation as b

where a and b are names such "Morning Star" and "Evening Star" respectively, "Rome" and "capital of Italy" respectively, "Cicero" and "Tully" respectively or "Superman" and "Clark Kent respectively. Let me suggest the following definition

(2) a is replaceable by b in sentences about B believing something iff aD(B)a

(this should be properly formalised, but I am now only testing my intuitions)



This definitely explains why the sentences

(3) Marek believes that Rome is a beautiful city
(4) Marek believes that the capital of twentieth century Italy is a beautiful city

are both true

but not sentences

(5) Cicero believes that Rome is a beautiful city (true perhaps)
(6) Cicero believes that the capital of twentieth century Italy is a beautiful city (false or nonsensical)

Simply, the two relevant descriptions have the same denotations for Marek but not for Cicero

There are four things to be said about this account of belief sentences. Two not so good and two quite good.

Not so good

(A) This solution is a capitulation. D(B) is not a general relation of meaning. It is not about meaning in a language. It is relativised to a particular believer. So it is not very general. So it may not be very interesting.

(B) You must be very careful how you formulate even informal paraphrases of D(B). For instance, you cannot say that aD(B)b means that B believes that "a" has the same denotation is "b". This would smack of a vicious circle, but this may not be the biggest problem. The problem is that the using of "believe" in the definition of aD(B)b could invite the same paradoxes as those which we tried to explain in the first place. Wherever we have belief we have intensionality

The solution is that "a has for B the same denotation as b" would be explained in behavioristic terms which would not include "believe". This is the philosophy of mind bit. I am very unwilling to recourse to behaviorism, because I like mental concepts and do not want to explain them away, but what can I do? I am just forced to accept it in this case, to explain the semantic puzzle.

Good

(C) This is a very simple solution at first glance (but complications lurk)

(D) It seems to save compositional semantics, although a reference is made to metalanguage, on both side of truth conditions. The intuitive sketch would look as follows.

The sentence "John believes Rome is a beautiful city" iff John believes Rome is a beautiful city and "Rome" denotes Rome for John

If it looks again like a vicious circle, but let me remind that the explication of "Rome" denotes for John Rome would be behaviouristic and "Rome" could be treated as a physical sound and denotation of Rome by "Rome" for John perhaps some physical disposition or co-occurance.

Am I satisfied with this solution? I will need to look at it again later