Macroscopic Power and Influence

Abstract

This chapter shows how causal powers and causal influences can be composed, both synchronically and asynchronically, to form composite powers and composite influences, which are a common feature of reductive explanation. Indeed, outside fundamental physics it is likely that many, if not all, the powers and influences mentioned will be composite rather than fundamental. A major part of this chapter involves defending the idea that composite influences can be composed of more basic component influences. In particular, it defends the idea from objections against the existence of composite and component forces. Since forces are paradigmatic examples of causal influence, these arguments will also be objections to the concept of composite influences more generally. Finally, having defended an account of the relation between composite and component powers, it show that this account defuses an argument recently advanced by Alexander Bird, who concludes that there are few, if any, true macroscopic powers.