 One way of approaching this question is to ask whether there is some principled procedure by which Aristotle generated his list of categories. For, if there is, then one could presumably assess his list of highest kinds by assessing the procedure by which he generated it. Unfortunately, with the exception of some suggestive remarks in the Topics, Aristotle does not indicate how he generated his scheme. Without some procedure by which one can generate his list, however, Aristotle’s categories arguably lack any justification. The issue is, of course, complicated by the fact that his list might be justified without some procedure to generate it — perhaps we can use a combination of metaphysical intuition and philosophical argumentation to convince ourselves that Aristotle’s list is complete. Nonetheless, without some procedure of generation Aristotle’s categories at least appear in an uneasy light. And as a matter of historical fact, the lack of any justification for his list of highest kinds has been the source of some famous criticisms. Kant, for instance, just prior to the articulation of his own categorial scheme, says: