The study of language becomes particularly attractive when it is not practised as an isolated descriptive enterprise, but when it has wide-ranging implications for the study of the human mind. Such is the spirit of this book. While "categorisation "may be the single most basic cognitive process in organisms, and as an area of inquiry, it is fundamental to Cognitive Science as a whole, at the other end of the spectrum, high-level cognition is organised and permeated by language, giving rise to categories that count and function as "concepts." Working from considering the philosophical assumptions of the cognitivist perspective, this study offers an argument for a very productive understanding of the relation between concepts, categories, and their theoretical models.