Full Idea
Psychologists have attempted to determine whether a concept of a category stores some causal knowledge about the members, some knowledge about their typical properties, or some knowledge about specific members.
Gist of Idea
Do categories store causal knowledge, or typical properties, or knowledge of individuals?
Source
Edouard Machery (Doing Without Concepts [2009], 1.3.2)
Book Reference
Machery,Edouard: 'Doing Without Concepts' [OUP 2009], p.19
A Reaction
I take there to be a psychological process of 'generalisation', so that knowledge of individuals is not and need not be retained. I am dubious about entities called 'properties', so I will vote for causal (including perceptual) knowledge.