Full Idea
People tend to positively categorise items that are consistent with their knowledge and to exclude items that are inconsistent, sometimes even overruling purely empirical sources of information.
Gist of Idea
People categorise things consistent with their knowledge, even rejecting some good evidence
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.173
A Reaction
The main rival to 'theory theory' is the purely empirical account of how concepts are acquired. This idea reports empirical research in favour of the theory theory (or 'knowledge') approach.