Full Idea
A comprehensive theory of thought will include such things as judgement and belief, as well as the mere grasp of propositions.
Gist of Idea
A theory of thought will include propositional attitudes as well as propositions
Source
Michael Dummett (Thought and Reality [1997], 4)
Book Reference
Dummett,Michael: 'Thought and Reality (Gifford Lectures)' [OUP 2006], p.51
A Reaction
This seems to make any theory of thought a neat two-stage operation. Beware of neatness. While propositions might be explained using concepts, syntax and truth, the second stage looks faintly daunting. See Idea 2209, for example.
Related Idea
Idea 2209 Belief is stronger, clearer and steadier than imagination [Hume]