Dispositions and Their Ascriptions

The central question addressed in this dissertation is, What, in the most general terms, is required for an object to have a disposition? In the formal mode, this is just the question, What are the truth conditions of disposition ascriptions, sentences of the form "N is disposed to M when C"? The dissertation begins by criticizing existing answers to this question, answers which consist in accounts of disposition ascriptions according to which they entail conditionals of one form or another. By developing examples due to C. B. Martin, Mark Johnston and others, it is argued that no conditional account of disposition ascriptions can be correct. Instead, a "Habitual Account" of disposition ascriptions is defended: an ascription "N is disposed to M when C" is true just in case N has some intrinsic property in virtue of which N Ms when C. This account is shown both to escape the criticisms levelled against conditional accounts, and to have independently persuasive motivation. ;Essential to the Habitual Account of disposition ascriptions is that the sentences that it makes use of, so-called "habitual sentences" of the form "N Ms when C," are not themselves to he understood as conditionals. How they are to be understood has been a matter of some debate in the recent semantics literature, and the dissertation engages with this debate by offering a novel account of the truth conditions of habitual sentences. It is argued that these sentences should be represented as containing an implicit, unpronounced adverbial quantifier, meaning something like "normally," "generally," or "typically," and a specific account of the semantic contribution made to habitual sentences by this quantifier is supplied. ;The dissertation ends by considering an issue in the metaphysics of dispositions, arguing, contrary to widespread philosophical opinion, that some dispositions are extrinsic properties of their bearers. This conclusion is shown not only to be compatible with the Habitual Account of disposition ascriptions, but also to be explained by it