 A system of categories is a complete list of highest kinds or genera. Traditionally, following Aristotle, these have been thought of as highest genera of entities (in the widest sense of the term), so that a system of categories undertaken in this realist spirit would ideally provide an inventory of everything there is, thus answering the most basic of metaphysical questions: “What is there?” Skepticism about our ability to discern a unique system of basic categories of ‘reality itself’ has led others to approach category systems not with the aim of cataloging the highest kinds in the world itself, but rather with the aim of elucidating the categories of our conceptual system or language. Thus Kant makes the shift to a conceptualist approach by drawing out the categories that are a priori necessary for any possible cognition of objects. Since such categories are guaranteed to apply to any possible object of cognition, they retain a certain sort of ontological import, although this application is limited to phenomena, not the thing in itself. After Kant, it has been common to approach the project of categories in a neutral spirit that Brian Carr (1987, 7) calls “categorial descriptivism”, as describing the categorial structure that the world would have according to our thought, experience, or language, while refraining from making commitments about whether or not these categories are occupied, or are ontically fundamental. Edmund Husserl approaches categories in something like this way, since he begins by laying out categories of meanings, which may then be used to draw out ontological categories (categories of possible objects meant) as the correlates of the meaning categories, without concern for any empirical matter about whether or not there really are objects of the various ontological categories discerned.