Abstract

What caused the event we report by saying “the window shattered”? Was it the baseball, which crashed into the window? Causal exclusionists say: many, many microparticles collectively caused that event—microparticles located where common sense supposes the baseball was. Unitary large objects such as baseballs cause nothing; indeed, by Alexander’s dictum, there are no such objects. This paper argues that the false claim about causal efficacy is instead the one that attributes it to the many microparticles. Causation obtains just where there is an “invariance”, a true generalization to the effect that had things been different with the putative cause, things would have been correspondingly different with the putative effect. But “correspondingly” here requires a rough metric. There must be a fact as to which alternative group events, involving many microparticles, would have departed less from the putative cause of the shattering, and which would have departed more. Surprisingly, there is no such fact