I'm particularly interested in research looking at how categories license inferences, and how, by including objects in a category, people reason about them in specific ways.
Constructionist Developmental Psychology , speciffically Piagetian and neo-Piagetian cognitive developmental theories, with their qualitatively different stages, try to indicate the nature of the stage shifts in concepts (categories) and then the coordinating and thinking about these new "units".
My perspective provides explicit, directly testable hypotheses (testable, through directly observable evidence of true proximate causes) on the very inception of these levels/stages -- that thus being the real ultimate basis of true categorical thinking unfolding with ontogeny. Here is a reasonable starting point:
Also see Book NOW the nearly complete collection of essays (RIGHT HERE) _B...
Read the Comment (1) ON that web page for that "book" (and the Reply to that Comment) for some quick qualitative introduction; but, then read everything else associate with the Ethogram Theory Project.
Based on clinical experience and on the findings of Cassirer, Piaget, Whitehead, Langer I have suggested a ‚Matrix of mental formation‘ buildt on categorial levels only.