Keywords: Convention; Custom; Rule-following; Projectibility (Induction); the Background of Intentionality.
In this paper I argue that there exist conventions of a peculiar sort, which are neither norms nor regularities of behaviour, partaking of both. I proceed as follows. After a sketchy analysis of the meaning of 'convention', I give some examples of the kind of phenomena I have in mind: bodily skills, know-how, taste and style, "habitus" (P. Bourdieu), «disciplines» (M. Foucault). Then I group some arguments supporting my claim: (i) considerations about the identity conditions of precedents (D. Lewis) and about the projectibility of predicates in inductive inference generally (N. Goodman); (ii) thoughts about rule-following (L. Wittgenstein); (iii) an examination of some of J. R. Searle's ideas about the «Background» of intentionality. I conclude with some remarks about the time-honoured antithesis 'nature' v. 'convention'.