Abstract
In this paper I consider the concept of an illocutionary rule - i.e., the rule of the form "X counts as 7 in context C" - and examine the role it plays in explaining the nature of verbal communication and the conventionality of natural languages. My aim is to find a middle ground between John R. Searle's view, according to which every conventional speech act has to be explained in terms of illocutionary rules that underlie its performance, and the view held by Ruth G Millikan, who seems to suggest that the formula "X counts as Y in context C" has no application in our theorizing about human linguistic practice. I claim, namely, that the concept of an illocutionary rule is theoretically useful, though not explanatorily basic. I argue that using the formula "X counts as Y in context C" we can classify illocutionary acts by what Millikan calls their conventional outcomes, and thereby make them susceptible to naturalistic explanation