This article draws up a genealogy of the notion of norms of thought, in the style of Bernard Williams (Truth and Truthfulness, 2002), from Locke to Peirce. It is shown how the idea of a norm was introduced into the Kantian context, going from the idea of ethical and juridical norms to that of norms of logic, which was taken up by the neo-Kantians and elaborated in the framework of James's ethics of beliefs.