In a previous post I noted that supervenience is probably the most popular conceptual tool used to explore the ontology of mind. The notion was introduced into mind by Donald Davidson who had a very interesting solution to some of the vexing problems of the time. I won’t go into that here, but let’s just say the target for him was to keep the universe sane, only exhibiting a single personality, while at the same time getting out of causal reduction. Supervenience allows us to see a way in which everything must be, in this case physical, without pressing the issue as to how it accomplishes this. It’s kind of like, I can see that Jones is clearly guilty and can clearly place him at the scene of the crime, even though I don’t have the slightest idea how he accomplished it.
The bankrobbery supervened on Jones, his mask, cloak, and bag of tools caught clearly on tape. But how he cracked the safe is an utter mystery.
While a great tool to explore the idea of physicalism with greater precision, it’s not universally accepted as having the ability to accomplish the goal of monism without reduction. J. Kim in particular makes a strong case that physicalism ultimately can’t survive absent causal reduction.