Stephen Mumford puts forward a new theory of dispositions, showing how central their role is in metaphysics and philosophy of science. Much of our understanding of the physical and psychological world is expressed in terms of dispositional properties--from the solubility of sugar to the belief that zebras have stripes. Mumford discusses what it means to say that something has a property of this kind, and how dispositions can possibly be real things in the world. His clear, straightforward, realist account reveals (...) them to be less mysterious than they seem, and shows that an understanding of dispositions is essential to an understanding of properties, causation, and scientific laws. (shrink)

George Molnar came to see that the solution to a number of the problems of contemporary philosophy lay in the development of an alternative to Hume's metaphysics. This alternative would have real causal powers at its centre. Molnar set about developing a thorough account of powers that might persuade those who remained, perhaps unknowingly, in the grip of Humean assumptions. He succeeded in producing something both highly focused and at the same time wide-ranging. He showed both that the notion of (...) a power was central and that it could serve to dispel a number of long-standing philosophical problems.Molnar's account of powers is as realist as any that has so far appeared. He shows that dispositions are as real as any other properties. Specifically, they do not depend for their existence on their manifestations. Nevertheless, they are directed towards such manifestations. Molnar thus appropriates the notion of intentionality, from Brentano, and argues that it is the essential characteristic of powers. He offers a persuasive case for there being some basic and ungrounded powers, thus ruling out the reducibility of the dispositional to the non-dispositional. However, he does allow that there are non-power properties as well as power properties. In this respect, his final position is dualistic.This is contemporary metaphysics of the highest quality. It is a work that was almost complete when its author died. It has been edited for publication by another specialist in the subject, Stephen Mumford, who has also provided an introduction that will allow non-specialists to become acquainted with the issues. David Armstrong, one of the greatest living metaphysicians and personal friend of George Molnar, has provided a Foreword. (shrink)

In this sequence of philosophical essays about natural science, the author argues that fundamental explanatory laws, the deepest and most admired successes of modern physics, do not in fact describe regularities that exist in nature. Cartwright draws from many real-life examples to propound a novel distinction: that theoretical entities, and the complex and localized laws that describe them, can be interpreted realistically, but the simple unifying laws of basic theory cannot.

With the possible exception of causation, disposition concepts are as prevalent in ordinary thought as any of the nomic concepts. Progress on their nature has been hard to come by. No doubt the difficulty of saying anything illuminating and suitably general about their nature is a function of their pervasiveness.

According to a standard characterization of dispositions, when a disposition is activated by a stimulus, a manifestation of that disposition typically occurs. For example, when flammable gasoline encounters a spark in an oxygen-rich environment, the manifestation of flammability—combustion—occurs. In the dispositions/powers literature, it is common to assume that a manifestation is an effect of a disposition being activated. (I use “disposition” and “power” interchangeably). I address two questions in this chapter: Could all manifestations be effects that involve things acquiring only (...) dispositional properties? And, is thinking of manifestations as contributions to effects preferable to thinking of them as effects? I defend negative responses to both questions. If all properties are dispositional, as the pandispositionalists claim, then any time the activation of a disposition results is something acquiring a new property, it results in something acquiring another disposition. Some worry that a vicious regress ensues (Swinburne, 1980; Bird, 2007a, 2007b: 132-46). While I believe that regress arguments can be addressed, my worry is that, on the pandispositionalist view, manifestations become unobservable. Thinking of manifestations as effects is problematic in cases where what actually occurs is not the kind of effect that the power is a power for, but rather a complex interaction of various powers. Because of this, some prefer to think of manifestations as contributions to effects (Molnar, 2003: 194-8; Mumford, 2009). I argue against this proposal on the ground that it introduces mysterious new entities into our ontology. In the end, the most plausible view is that a single kind of power can have different kinds of effects, some of which involve the instantiation of non-dispositional properties. I proceed as follows. In the first section of this chapter, I show that the philosophical concept of a manifestation is the concept of an effect. In the second section, I argue against the claim that all manifestations involve instantiations of only dispositional properties. In the third section, I argue against the view that manifestations are contributions rather than effects. (shrink)