Online research in philosophy

If dispositions are conceived as properties of systems that refer to possible causal relations, dispositions can be used in singular causal explanations. By means of these dispositional explanations, we can explain behavior B of a system x by (i) referring to a situation of type S that triggered B, given that x has a disposition D to do B in S, or (ii) by referring to a disposition D of x to do B in S, given that x is in a situation of type S. Dispositional explanations are adequate and indispensable explanations: they can explain behavior B without explicitly referring to the underlying causal basis in x that constitutes a disposition to do B. Radical Behaviorist explanations are a sort of dispositional explanations, but the dispositional model is not restricted to these explanations. The dispositional model is compatible with, or can be applied to, several research programs.

Subjunctive conditionals have their uses, but constituting the meaning of dispositional predicates is not one of them. More germane is the analysis of dispositions in terms of "bases"--except that past efforts to maintain an ontic gap between dispositions and their bases, while not wholly misguided, have failed to appreciate the semantic birthright of dispositional concepts as a species of theoretical construct in primitive science.

Dispositional essentialists are typically committed to two claims: that properties are individuated by their causal role (‘causal structuralism’), and that natural necessity is to be explained by appeal to these causal roles (‘dispositional actualism’). I argue that these two claims cannot be simultaneously maintained; and that the correct response is to deny dispositional actualism. Causal structuralism remains an attractive position, but doesn’t in fact provide much support for dispositional essentialism.

In explaining what happens, we commonly use both dispositional and causal concepts. A historian might refer to the belligerent disposition of a nation-state, and use this to explain why a neighbouring state was so anxious to seek an apparently unwise alliance. A physicist might have occasion to mention the disposition of a metal to expand when heated, and use this to explain why a measurement was inaccurate when taken in abnormally hot conditions. The contexts of explanation – physics and history – are very different, but the concepts are recognisably causal and dispositional in both cases.

We argue that the inference from dispositional essentialism about a property (in the broadest sense) to the metaphysical necessity of laws involving it is invalid. Let strict dispositional essentialism be any view according to which any given property’s dispositional character is precisely the same across all possible worlds. Clearly, any version of strict dispositional essentialism rules out worlds with different laws involving that property. Permissive dispositional essentialism is committed to a property’s identity being tied to its dispositional profile or causal role, yet is compatible with moderate interworld variation in a property’s dispositional profile. We provide such a model of dispositional essentialism about a property and metaphysical contingency of the laws involving it.

The basic principles of dispositional essentialism do not require that the fundamental spatiotemporal relations are dispositional in nature. Nevertheless, Bird (who defends dispositional monism) argues that they possess dispositional essences in virtue of the fact that the obtaining of these relations can be characterised by the satisfaction of a certain counterfactual. In this paper I argue that his suggestion fails, and so, despite his attempt, the case of the spatiotemporal relations remains the ‘big bad bug’ for the thesis of dispositional monism.

Dispositional essentialists claim that dispositional properties are essentially dispositional: a property would not be the property it is unless it carried with it certain dispositional powers. Categoricalists about dispositional properties deny this, asserting that the same properties might have had different dispositional powers, had the contingent laws of nature been otherwise.

: It is widely thought that dispositional properties depend upon categorical properties; specifying the nature of this dependency, however, has proven a difficult task. The dependency of dispositional properties upon categorical properties also presents a challenge to the thesis of Physicalism: If the physical sciences only tell us about the dispositional properties of the objects they study and if dispositional properties depend upon categorical properties, then it appears that there will be kind of property—categorical properties—that will escape description by the physical sciences. This paper argues that a new theory of dispositional and categorical properties, a theory put forth by C.B. Martin and John Heil, solves both of these problems: It presents a way of understanding the sense in which dispositional properties depend upon categorical properties that has major advantages over more popular accounts of this dependency and it also provides a new and interesting Physicalist response to the challenge presented by categorical properties.

According to a model defended by some authors, dispositional predicates, or concepts, can be legitimately used in causal explanations, but such a use is not necessary. For every explanation couched in dispositional terms, there is always a better, and complete, explanation that makes use of a different vocabulary, that of categorial bases. In what follows, I will develop this view, and then argue that there is a kind of use of dispositions in explanations that does not fall within this model. That is, I will argue that we would miss some explanations if we were to forsake dispositional concepts and dispositional explanations.