Mind: A Brief Introduction (John R. Searle) / quote 30 of 138
Epiphenomenalism: consciousness as froth on the wave
Some philosophers who think that we could explain how consciousness is caused by brain processes cannot see how consciousness could have any causal powers of its own. Granted that somehow or other consciousness, and mental phenomena generally, are dependent on brain processes, it is hard to see how they could cause bodily movements or cause anything in the physical world. The view that mental states exist but are causally inert is called “epiphenomenalism.” On this view consciousness exists alright, but it is like the froth on the wave or the flash of sunlight reflected off the surface of the water. It is there but it does not really matter. It is an epiphenomenon. But this seems too counterintuitive. Every time I decide to raise my arm, it goes up. And it is not a random or statistical phenomenon. I do not say, “Well, that’s the thing about the old arm. Some days she goes up and some days she doesn’t.” The problem is to show how something not a part of the physical world could have such effects on the physical world.