ABSTRACT In recent years, a number of philosophers have promoted a quasi-realist (or projectivist) interpretation of Hume's theory of causation. In this paper, we argue against the quasi-realist interpretation of Hume, on the grounds that there is a direct clash between a fundamental element of Hume's system (his empiricist theory of content) and one of the main constraints that governs any form of quasi-realism (and so a fortiori, quasi-realism about causation).