Machines of Creation and Annihilation.

A prime motivation behind epiphenomenalism is the belief that only such an account of mind allows for both the genuine non-reductive existence of mental states and the causal closure of the physical world. Materialism gives us causal closure, but denies the reality of the mental. Interactionism gives us the reality of the mental, but only at the cost of sacrificing a basic presupposition of modern science.

Causal closure refers the assumed fact that every physical event has an adequate physical cause. Phenomena in our brains and bodies, like everything else, can be adequately explained by appealing to physical causality. If we assume interactionism to be the case, then there is some tiny bit of energy in our brains that are caused not by physiological processes. When I will my arm to move, there is suddenly in the universe some bit of energy that was not there before. I am a machine of creation, making radically new additions to the universe every time my mind interacts with my body.

Epiphenomenalism it is said,avoids this purportedly absurd conclusion. But does it?

If interactionism is true, then my mind/brain is a machine of creation, but the process works the other way as well. When my brain interacts with my mind physical energy is expended that produces a mental result. Interactionism thus makes me a machine of annihilation as well as creation. Some little bit of energy is expended every time my brain interacts with my mind.

One might think this just makes the situation for the interactionist worse, or at least no better. But what I want to stress is that this latter aspect of interactionism is present also for the epiphenomenalist. Epiphenomenalism is not parallellism. On epiphenomenalist views there is a causal relationship between body and mind, its just that it goes only one way.

So if the causal closure of the physical is assumed, epiphenomenalism must go the way of interactionism, into the dust heap of scientifically disreputable theories of mind.

A response to this argument is to deny that the causal relation between brain and mind involves any real transfer of energy. No one really knows what a "transfer of energy" really is and those of a Humean persuasion may well argue that on a fundamental level there is really no such thing as "energy." There are only lawlike regularities. But if this sort of reply is adequate to account for my existence as an engine of annihilation, why can it not also be used in defense of the creation side of the mind/body relationship.