Abstract

According to Peter van Inwagen, free will is a mystery because free will appears to be both incompatible with determinism and indeterminism. Drawing on Aquinas’s account of a free human choice, I argue that van Inwagen’s dilemma is not inescapable. I argue that there might be a weaker version of determinism that is both weak enough to be compatible with a human agent’s choice being undetermined and strong enough to be compatible with a human agent’s choice being self-determined. In describing this weaker version of determinism, I rely on David Lewis’s idea of “comparative possibilities”: the idea that there might be possibilities that are “more possible” than others. The idea is this: If this weaker version of determinism is true, there are many possible futures for the agent, without there being many equally possible futures for that agent. Instead, there is a possible future that is more possible than any other possible future, that is, a possible future that is the most possible future for that agent.