Full Idea
Philosophy is a department of logic.
Gist of Idea
Philosophy is a department of logic
Source
A.J. Ayer (Language,Truth and Logic [1936], Ch.2)
Book Reference
Ayer,A.J.: 'Language, Truth and Logic' [Penguin 1974], p.76
A Reaction
Personally I would invert that. Philosophy is concerned with human rationality, of which precise logic appears to be a rather limited subdivision. I see philosophy as the 'master' subject, not the 'servant' subject (as Locke had implied).