Full Idea
Some kinds of knowledge are probably directly incorporated into the category representation and used in normal, fast decisions about objects. Other kinds of knowledge, however, may come into play only when it has been solicited.
Gist of Idea
Some knowledge is involved in instant use of categories, other knowledge in explanations
Source
Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
Book Reference
Murphy,Gregory L.: 'The Big Book of Concepts' [MIT 2004], p.168
A Reaction
This is a summary of empirical research, but seems to fit our normal experience. If you see a hawk, you have some instant understanding, but if you ask what the hawk is doing here, you draw more widely.