Full Idea
The nail in the coffin of the classical theory is its lack of explanatory power. For example it doesn't explain the fact that typical x's are categorised more quickly and more reliably than atypical x's.
Gist of Idea
Classical theory can't explain facts like typical examples being categorised quicker
Source
Edouard Machery (Doing Without Concepts [2009], 4.1.3)
Book Reference
Machery,Edouard: 'Doing Without Concepts' [OUP 2009], p.80
A Reaction
[He cites Rosch and Mervis: 1975:ch 5] This research launched the 'prototype' theory, which has since been challenged by the 'exemplar' and 'theory theory' rivals (and neo-empiricism, and idealisation).