 Regardless of whether we are studying categories of meanings or of objects, Husserl is quite clear that the study of categories, for him, is an entirely a priori matter; the categories of meanings and objects alike “arise … solely in relation to our varying thought-functions: their concrete basis is solely to be found in possible acts of thought, as such, or in the correlates which can be grasped in these” (1913 [2000], 237). As he puts it later, in the Ideas, the study of categories is a study of essences, based in essential insights about the types of meanings and correlative types of things. Such studies of essence may be conducted by way of imaginative variation of cases, independently of any matter of fact, including whether or not there actually is anything of the ontological kinds distinguished (1913 [1962], 51). Thus Husserl’s ontological categories, in this sense, are descriptive categories of highest essences of possible things (that might fall under those essences), and do not purport to provide an inventory of what things actually exist (as a matter of empirical fact).