Why difference-making mental causation does not save free will

ABSTRACT Many philosophers take mental causation to be required for free will. But it has also been argued that the most popular view of the nature of mental states, i.e. non-reductive physicalism, excludes the existence of mental causation, due to what is known as the ‘exclusion argument’. In this paper, I discuss the difference-making account of mental causation proposed by [List, C., and Menzies, P. 2017. “My Brain Made Me Do It: The Exclusion Argument Against Free Will, and What’s Wrong with It.” In H. Beebee, C. Hitchcock, & H. Price (eds.), Making a Difference: Essays on the Philosophy of Causation. Oxford Scholarship Online: Oxford University Press], who argue that their account not only solves the problem of causal exclusion but also saves free will. More precisely, they argue that it rebuts what they call ‘the Neurosceptical Argument’, the argument that if actions are caused by neural states and processes unavailable to us, there is no free will. I argue that their argument fails for two independent reasons. The first reason is that they fail to show that difference-makers are independent causes. The second reason is that physical realizers of mental states can be individuated in a way that makes both mental states and their realizers difference-makers.