Combining Texts

Ideas for 'Truth and Ontology', 'Introduction to 'Language Truth and Logic'' and 'Can Mechanisms Replace Laws of Nature?'

unexpand these ideas     |    start again     |     choose another area for these texts

display all the ideas for this combination of texts


3 ideas

19. Language / A. Nature of Meaning / 5. Meaning as Verification
A statement is meaningful if observation statements can be deduced from it [Ayer]
     Full Idea: In the improved version, a statement was verifiable, and consequently meaningful, if 'some observation-statement can be deduced from it in conjunction with certain other premises, without being deducible from those other premises alone'.
     From: A.J. Ayer (Introduction to 'Language Truth and Logic' [1946], p.15)
     A reaction: I.Berlin showed that any statement S could pass this test, because if you assert 'S' and 'If S then O', these two statements entail O, which could be some random observation. Hence a 1946 revised version had to be produced.
Directly verifiable statements must entail at least one new observation statement [Ayer]
     Full Idea: A statement is directly verifiable if it is either itself an observation-statement,or is such that in conjunction with one or more observation-statements it entails at least one observation-statement which is not deducible from these other premises alone.
     From: A.J. Ayer (Introduction to 'Language Truth and Logic' [1946], p.17)
     A reaction: This is the 1946 revised version of the Verification Principle, which was then torpedoed by an elaborate counterexample from Alonzo Church. Ayer thereafter abandoned attempts to find a precise statement of it.
The principle of verification is not an empirical hypothesis, but a definition [Ayer]
     Full Idea: I wish the principle of verification to be regarded, not as an empirical hypothesis, but as a definition.
     From: A.J. Ayer (Introduction to 'Language Truth and Logic' [1946], p.21)
     A reaction: This is Ayer's attempt to meet the well known objection of 'turning the tables' on his theory (by asking whether it is tautological or empirically verifiable). However, if it is just a definition, then presumably it is completely arbitrary…