 Others have taken the variety of category systems explicitly offered or presupposed by philosophers as mere evidence of the particular presuppositions of their thought, or prejudices of their age – not as evidence about anything to do with the world and its divisions. Thus, e.g., Stephan Körner’s discussion of categorial frameworks is designed to make explicit how a thinker’s framework categorizes objects, making use of certain individuative principles, and making clear his reasons for holding that framework (1970, 10). R. G. Collingwood, in similar vein, treats the task of metaphysics generally as merely uncovering the “presuppositions underlying ordinary science” (1940 [1998]).