This paper presents an 'internal' criticism of Winch's seminal 'Understanding a Primitive Society'. It distinguishes between two contrasting approaches to critical social understanding: (1) the metaphysical approach, central to the whole tradition of critical philosophy and critical social theory from Kant, through Marx to the Frankfurt School and contemporary theorists such as Habermas and Searle; (2) the descriptive approach, advocated by Winch, and which derives from Wittgenstein's critique of philosophical theory. It is argued, against a long tradition of 'critical theory' depicting Wittgenstein's philosophy as irredeemably 'conservative', that the descriptive approach is perfectly apt for generating a critical understanding of central Western institutions. Rather than seeking to provide an explanatory theory through which to discern what allegedly is imperceptible to theoretically unaided perception (i.e. the metaphysical approach), the descriptive approach aims for a 'perspicuous presentation' of our everyday practices and institutions in such a way as to see their 'irrational' and 'alienating' dimensions. Winch's basic position in 'Understanding a Primitive Society' is endorsed, but it is argued that ultimately he fails in his descriptive intent. In place of the Christian prayer analogy that Winch invokes in order to make sense of Zande witchcraft, it is proposed that Western commodity production and exchange provide a more appropriate, instructive, and critical comparison.