Linguistic relativism is the thesis that the grammatical structures of different languages imply different conceptions of reality. In this paper we critically discuss one form of linguistic relativism, which argues that grammatical differences between the English and Yoruba language exhibit differences in how English and Yoruba speakers 'see' reality (namely in terms of 'spatiotemporal particulars' and 'sortal particulars', respectively). We challenge the idea that linguistic relativism is an empirical thesis, i.e., a thesis that is substantiated through anthropological examples. We show that linguistic relativism is based on two assumptions: firstly, that the purpose of language is to describe the world; secondly, that being able to speak presupposes an ontological theory of the ultimate constituents of the world. We argue that the attempt to extract the outline of that theory from the language inevitably distorts the portrayal of language-using practice itself. © 2006 Elsevier Ltd. All rights reserved.