Full Idea
All comparisons terminate in, and are concerned about those simple ideas, either of sensation or reflection; which I think to be the whole material of all our knowledge.
Gist of Idea
Comparisons boil down to simple elements of sensation or reflection
Source
John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 2.25.09)
Book Reference
Locke,John: 'Essay Concerning Human Understanding', ed/tr. Nidditch,P.H. [OUP 1979], p.323
A Reaction
This seems to be an ancestor of logical atomism. Hume is inclined to make his 'atoms' strictly empirical (as 'impressions'), but Locke also allows simples of reflection, which may be a priori conceptual atoms.