Liar - Sentences and statements
Readings
- Goldstein, L. (1992). 'This statement is not true' is not true. Analysis. 52.1, 1-5. link
Distinguishing between between sentences and statements / propositions.
@哲學提高學生的分析能力。
Philosophy improves the analytical abilities of students.@
- Taking statements and not sentences as truth-bearers.
Modified versions of the Liar sentences
@(L4) Sentence L4 expresses a false statement.@
The corresponding version of the strengthened liar:
@(L5) Sentence L5 does not express a true statement.@
Why is this supposed to help?
- The same sentence might express a statement in one context but fails to do so in another context. "That man is a pervert."
- So one might argue that although L5 does not express a true statement, one can report that fact using the very same sentence type and succeeds in making a true statement.
@(L6) Sentence L5 does not express a true statement.@
Three objections - L5 does express a statement
- Why is it that one token expresses a statement whereas the other one does not? Normal explanations of expressive failures do not seem to apply here, e.g. referential failure.
- A subject-predicate sentence Fa expresses a statement if a ("L5") succeeds in denoting an object and F ("does not express a true statement") expresses a property. This applies to L5.
- Samesaying principle - if A says the same thing as B, and A is true (false), then B is also true (false). Rejecting the samesaying principle makes it unclear how truth is to be explained. (The truth of a statement depends on what is said and the facts.)