Full Idea
Analytic judgements say nothing in the predicate that was not already thought in the concept of the subject, though not so clearly and with the same consciousness. If I say all bodies are extended, I have not amplified my concept of body in the least.
Gist of Idea
Analytic judgements say clearly what was in the concept of the subject
Source
Immanuel Kant (Prolegomena to Any Future Metaphysic [1781], 266)
Book Reference
Kant,Immanuel: 'Prolegomena to Any Future Metaphysic', ed/tr. Lucas,Peter G. [Manchester UP 1971], p.16
A Reaction
If I say all bodies are made of atoms, have I extended my concept of 'body'? It would come as a sensational revelation for Aristotle, but it now seems analytic.