Does Anything Break Because it is Fragile? :: Philosophy Philosophers Essays

Does Anything Break Because it is Fragile? ABSTRACT: I maintain that dispositions are not causally relevant to their manifestations. The paper begins with a negative argument, which is intended to undermine David Lewis’ recent attempt to restore causal potency to dispositions by identifying their instantiations with the instantiations of their causal bases. I conclude that Lewis’ attempt to vindicate the causal credentials of dispositions meets obstacles that are analogous to (though importantly different from) those that beset Donald Davidson’s attempt to accord a causal role to the mental. I then consider an argument recently given by Frank Jackson against the causal relevance of dispositions (to their manifestations). Jackson’s argument relies on a conception of dispositions that is not likely to be shared by those who defend their causal relevance. I sketch an alternative conception of dispositions that links them more closely to their causal bases, but argue that even on this model disposition s are causally impotent. The paper closes with a defense of the claim that dispositions, in spite of their causal irrelevance to their manifestations, are nevertheless causal-explanatorily relevant to them. We regard dispositions as being causally responsible for their manifestations. We say that the glass broke because it was fragile, that the rubber band stretched because it is elastic, and that the arsenic killed him because it was lethal. Some philosophers have denied this. According to them, dispositions are causally irrelevant to the effects in terms of which they are defined. This view was defended by Elizabeth Prior, Robert Pargetter and Frank Jackson, and has been (tentatively) endorsed by David Lewis. According to them, fragility is the second-order property of having some or other first-order property (e.g., a given molecular structure) that tends to cause breaking under certain circumstances. But then, they infer, it is this first-order feature (the `causal basis' of the glass's fragility), and not fragility itself, that is responsible for causing the breaking. Fragility is thus conceptually after the fact as concerns the causation of breaking: the glass counts as being fragile only in consequence of its having some other, first-order property that is causally responsible for its breaking when struck. Lewis has always seemed uneasy with this view. He has called it a "disagreeable oddity" that must be dispatched if the identification of dispositions with second-order properties is to win our unequivocal support. In a recent paper, he takes himself to have done just that.