David Robb

This paper is an articulation and defense of a trope-bundle theory of material objects. After some background remarks about objects and tropes, I start the main defense in Section III by answering a charge frequently made against the bundle theory, namely that it commits a conceptual error by saying that properties are parts of objects. I argue that there’s a general and intuitive sense of “part” in which properties are in fact parts of objects. This leads to the question of qualitative unity: in virtue of what are certain properties unified as parts of an object? In Section IV I defend an account of unity for complex material objects. It turns on the thesis that the properties of such objects are structural properties. After addressing some objections, I turn in Section V to the question of unity for simple material objects. Here a different and more radical account is needed, for simples, since they do not have structural properties, are not subsumed by the account of Section IV. I defend the view that a simple object just is a simple property, so that identity delivers the desired unity.

E.J. Lowe has recently proposed a model of mental causation on which mental events are emergent, thus exerting a novel, downward causal influence on physical events. Yet on Lowe's model, mental causation is at the same time empirically undetectable, and in this sense is "invisible". Lowe's model is ingenious, but I don't think emergentists should welcome it, for it seems to me that a primary virtue of emergentism is its bold empirical prediction about the long-term results of human physiology. Here I'll try to restore emergentism's empirical status, but my broader aim is to use Lowe's model to explore some central topics in the mental causation debate, including the "causal closure" of the physical world and the nature of causal powers.