Introduction

Since the death of strong reductionism, philosophers of science have expanded the horizons of their understandings of the physical, mental, and social worlds, and the complex relations among them. To give one interesting example, John Dupré has endorsed a notion of downward causation: ‘higher-level’ events causing events at a ‘lower’ ontological level. For example, my intention to type the letter ‘t’ causes the particular motions experienced by all the atoms in my left forefinger as I type it. The proper explanation of the motions of an atom at the tip of my forefinger primarily involves my intentions, rather than (for example) the immediately preceding motions of other nearby atoms, or any other such particle-level events.

While this is a natural enough idea on the face of it, such downward causation has seemed to be in tension, or outright conflict, with another compelling intuition, which Dupré calls causal completeness.