Kant's Categories Reconsidered
ABSTRACT: Adopting a Quinean criterion of ontological commitment, I consider the question of the ontological commitment of Kant's theory of our a priori knowledge of objects. Its direct concern is the customary view that the ontology of Kant's theory of knowledge in general, whether a priori or empirical, must be thought in terms of the a priori conditions or representations of space, time, and the categories. Accordingly, this view is accompanied by the customary interpretation of ontology as consisting of Kantian "appearances" or "empirical objects." I argue against this view and interpretation. My argument turns on the opposition between the necessity and universality of the a priori and the particularity and contingency of the existent. Its main point is that the a priori can remain necessary and universal only if the existence of objects is kept distinct from it.
To the extent that category theory, i.e. that there are certain predicates of things that are fundamental to our thought about objects in general, has been based on our thought of objects of possible experience, it has been highly suspect. This is the negative thesis of this paper. Over the years, philosophical inventiveness has produced various schemes of predicates which challenge the claims of necessity that have been made on behalf of the scheme we employ for such objects-a scheme of substances that are involved in causal action and interaction. If no particular scheme is necessary, perhaps it is not necessary that we employ any scheme at all.
Kant's theory of categories is no different from any other category theory in this regard. Its dependence on what Kant calls the logical functions of judgment doesn't change matters. If it is primarily experience that the categories are supposed to help make possible, these functions are indistinguishable from logical forms of of judgment, and such forms, belonging as they do to formal, or what Kant calls general, logic, a logic that abstracts from all content of knowledge in general, cannot instruct us with respect to fundamental predicates of things.
This negative thesis suggests a positive one, namely, that categories should be argued for as necessary conditions of the possibility of a knowledge that is distinct from experience, viz., a priori knowledge. It is only in the context of such an argument that the categories can be shown to be required for possible experience as well.
Before we turn our attention to our separate arguments in support of the two theses which we are attributing to Kant, we should first consider an objection of interpretation that applies to both attributions. It might be noted that for Kant the objective validity of the categories is not completely established until they are shown to be necessary conditions of the possibility of experience (e.g. B 161). (1) It might then be asked why the demonstration of this necessity cannot be separated from...