Sociological interest in questions of'reality' and 'knowledge' is thus initially justifies by the fact of their social relativity. What is 'real' to a Tibetan monk may not be 'real' to an American businessman. The 'knowledge' of the criminal differs from the 'knowledge' of the criminologist. It follows that specific agglomerations of 'reality' and 'knowledge' pertain to specific social contexts, and that these relationships will have to be included in an adequate sociological analysis of these contexts. The need for a 'sociology of knowledge' is thus already given with the observable differences between societies in terms of what is taken for granted as 'knowledge' in them.