The aim of this article is to see whether we can account for the normativity of law within the framework of legal positivism and whether the idea of a social convention could be of help in this endeavour. I argue, inter alia, that we should distinguish between (α) the problem of accounting for the normativity of law, conceived as a necessary property of law, and (β) the problem of accounting for the use of normative legal language on the part of legal actors; that the debate about the normativity of law, which mainly concerns (α), is more or less identical to the debate between legal positivists and non-positivists; that one cannot account for the normativity of law, conceived along the lines of (α), within the framework of legal positivism, and that the question of the normativity of law considered within the framework of legal positivism is not an open question.