Full Idea
According to theory theorists, a concept of a category stores some knowledge that can explain the properties of the category members.
Gist of Idea
Theory Theory says category concepts are knowledge stores explaining membership
Source
Edouard Machery (Doing Without Concepts [2009], 4.4.1)
Book Reference
Machery,Edouard: 'Doing Without Concepts' [OUP 2009], p.101
A Reaction
This is the account of essentialism which I defended in my PhD thesis. So naturally I embrace a theory of the nature of concepts which precisely dovetails with my view. I take explanation to be the central concept in metaphysics.