Full Idea
Ideas are whatsoever is the object of a man's understanding whenever a man thinks.
Gist of Idea
Ideas are the objects of understanding when we think
Source
John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 1.01.08)
Book Reference
Locke,John: 'Essay Concerning Human Understanding', ed/tr. Nidditch,P.H. [OUP 1979], p.47
A Reaction
Robinson quotes this to show how infuriatingly vague Locke is about ideas. Obviously they can be further analysed into a variety of mental events, ranging from inputs to reactions to judgements.
Related Idea
Idea 23660 The theory of ideas, popular with philosophers, means past existence has to be proved [Reid]