 The heart of a Davidsonian theory of interpretation is, of course, a Tarskian truth theory. But a truth theory provides only the formal structure on which linguistic interpretation is based: such a theory needs to be embedded within a broader approach that looks to the interconnections between utterances, other behaviour and attitudes; in addition, the application of such a theory to actual linguistic behaviour must also take account of the dynamic and shifting character of such behaviour. This latter point is easily overlooked, but it leads Davidson to some important conclusions. Ordinary speech is full of ungrammatical constructions (constructions that may even be acknowledged to be ungrammatical by the speaker herself), incomplete sentences or phrases, metaphors, neologisms, jokes, puns and all manner of phenomena that cannot be met simply by the application to utterances of a pre-existing theory for the language being spoken. Linguistic understanding cannot, then, be a matter simply of the mechanical application of a Tarski-like theory (although this is just what Davidson might be taken to suggest in the early essays). In papers such as ‘A Nice Derangement of Epitaphs’ (1986), Davidson addresses just this point, arguing that while linguistic understanding does indeed depend upon a grasp of the formal structure of a language, that structure always stands in need of modification in the light of actual linguistic behaviour. Understanding a language is a matter of continually adjusting interpretative presuppositions (presuppositions that are often not explicit) in accord with the utterances to be interpreted. Furthermore, this calls upon skills and knowledge (imagination, attentiveness to the attitudes and behaviour of others, knowledge of the world) that are not specifically linguistic and that are part of a more general ability to get on in the world and in relation to others – an ability that also resists any formal explication. In ‘A Nice Derangement of Epitaphs’, Davidson puts this point, in provocative fashion, by claiming that ‘there is no such thing as a language’ (adding the immediate qualification ‘not if a language is anything like what many philosophers and linguists have supposed’). Put less provocatively, the essential point is that linguistic conventions (and in particular linguistic conventions that take the form of agreement over the employment of shared syntactic and semantic rules), while they may well facilitate understanding, cannot be the basis for such understanding. 