This paper examines two practices – the Roman Catholic Practice of Eucharist and the game Dungeons and Dragons – to show how social critique can be mounted from within a practice. It begins by relating Alasdair MacIntyre’s notion of tradition to his earlier analysis of ideology and to the notion of ideology in general. The paper then tackles two dominant forms of ideology – Commodity Fetishism and Scientism – and shows how both Eucharist and Dungeons and Dragons promote critical thinking to resist those ideologies. In the process, it denies the Althusserian-Foucauldian analysis of ideology as mere materiality and defends a conception of ideology as material and ideal.