Downward causation and supervenience: the non-reductionist’s extra argument for incompatibilism

Agent-causal theories of free will, which rely on a non-reductionist account of the agent, have traditionally been associated with libertarianism. However, some authors have recently argued in favor of compatibilist agent-causal accounts. In this essay, I will show that such accounts cannot avoid serious problems of implausibility or incoherence. A careful analysis of the implications of non-reductionist views of the agent (event-causal or agent-causal as they may be) reveals that such views necessarily imply either the denial of the principle of supervenience or the assumption of bottom-level indeterminism. I will contend that the former alternative comes at a high cost, while the latter is quite plausible. Therefore, providing that they accept the condition of the truth of indeterminism, non-reductionist accounts of the agent do not have to contradict our scientific worldview. Interestingly, while they should be taken seriously by anyone who is concerned with the passivity of the agent’s role under a reductionist scenario, non-reductivist accounts end up contributing an extra incompatibilist argument to the free will debate.