Full Idea
The analytic theory of the apriority of logic arose indirectly, as a by-product of the attempt to explain in what a grasp of the meaning of the logical constants consists.
Gist of Idea
That logic is a priori because it is analytic resulted from explaining the meaning of logical constants
Source
Paul Boghossian (Analyticity Reconsidered [1996], §III)
Book Reference
-: 'Nous' [-], p.11
A Reaction
Preumably he is referring to Wittgenstein's anguish over the meaning of the word 'not' in his World War I notebooks. He first defined the constants by truth tables, then asserted that they were purely conventional - so logic is conventional.