Philosophy is 'the study of the most general and abstract features of the world and categories with which we think: mind, matter, reason, proof, truth, etc. In philosophy the concepts with which we approach the world themselves become the topic of enquiry' (Blackburn, 1996, p. 286). Such concepts shape, and are shaped by, the material and representational construction of socionature (p. 2), and are embedded in the language, discourse and ideology we consciously or subconsciously use to account for the nature and workings of the world and our place and destiny within it. The philosophy of geography studies the concepts that structure geographical knowledge in an attempt to lay bare the subject's foundations and presuppositions. It reveals a diversity of approaches that this chapter will explore.