Full Idea
The classical view of concepts has been tied to traditional logic. 'Fido is a dog and a pet' is true if it has the necessary and sufficient conditions for both, ...but there is empirical evidence that people do not follow that rule.
Gist of Idea
Classical concepts follow classical logic, but concepts in real life don't work that way
Source
Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
Book Reference
Murphy,Gregory L.: 'The Big Book of Concepts' [MIT 2004], p.26
A Reaction
Examples given are classifying chess as a sport and/or game, and classifying a tree house (which is agreed to be both a building and not a building!).