Full Idea
We can overthrow speculative philosophy, and see that the function of philosophy is wholly critical.
Gist of Idea
Philosophers should abandon speculation, as philosophy is wholly critical
Source
A.J. Ayer (Language,Truth and Logic [1936], Ch.2)
Book Reference
Ayer,A.J.: 'Language, Truth and Logic' [Penguin 1974], p.65
A Reaction
This seems to imply that we CAN speculate, which appeared to be rendered impossible by the verification principle. Personally I think speculation is central to philosophy, but Ayer should always stand as a warning against bogus truth-claims.