Abstract
Many common arguments for physicalism begin with the principle that the cosmos is “causally closed.” But how good are the arguments for causal closure itself? I argue that the deductive, a priori arguments on behalf of causal closure tend to beg the question. The extant inductive arguments fare no better. They commit a sampling error or a non-sequitur, or else offer conclusions that remain compatible with causal openness. In short, we have no good arguments that the physical world is causally closed.