 One might, of course, turn to cognitive science to attempt to address the question of whether there is a fixed system of categories determined by our cognitive structure. And indeed, discussions of categories also play an important role in cognitive science, where the goal is not to discover the fundamental categories of being, but rather the means by which experiencers come to categorize their world. Here, debates have centered on how humans in fact come to group things into categories – whether this involves lists of definitional (observable or hidden) features, resemblance to prototypes, prominent features weighted probabilistically, etc. Debates also concern the relation between conceptual and linguistic categories, which levels of category are more basic, whether there is a most basic set of categories, whether or to what extent categorizations are consistent across cultural groups, and whether or not some fundamental categories are innate. The psychologist Susan Carey (2011) has engaged in a number of studies on infants and primates which, she argues, suggest that there are a number of concepts of ‘core cognition’ that are innate, designed to represent certain classes of entity in the world, and that are shared across pre-linguistic human infants, adults, and other primates. These include the concept of object (taken as a sortal concept that makes use of boundedness and spatio-temporal continuity in individuation), quantity, intentional agency, and causation. For further discussion of the debates about categorization in cognitive science see Lakoff (1987) and Rakison and Oakes (2003).