Recent interest amongst critical human geographers in postcolonial theory has been framed by a concern for the relationship between ‘polities’ and ‘theory’. In this paper I address debates in the field of colonial discourse analysis in order to explore the connections between particular conceptions of language and particular models of politics to which oppositional academics consider themselves responsible, The rhetorical representation of empowerment and disempowerment through figures of ‘speech’ and ‘silence’, respectively, is critically examined in order to expose the limits of this representation of power relations. Through a reading of Gayatri Chakravorty Spivak's account of the dilemmas of subaltern representation, contrasted to that of Benita Parry, and staged via an account of their different interpretations of the exemplary postcolonial fictions of J M Coetzee, it is argued that the deconstruction of the conventional metaphories of speech and silence calls into view the irreducible textuality of the work of representation. This implies that questions about institutional positionality and academic authority be kept squarely in sight when discussing the problems of representing the struggles and agency of marginalised social groups. It is suggested that the continuing suspicion of literary and cultural theory amongst social scientists for being insufficiently ‘materialist’ and/or ‘political’ may serve to reproduce certain forms of institutionally sanctioned disciplinary authority.