Mind: A Brief Introduction (John R. Searle) / quote 39 of 138
Dualism versus the conservation of energy
It seems impossible to make substance dualism consistent with modern physics. Physics says that the amount of matter/energy in the universe is constant; but substance dualism seems to imply that there is another kind of energy, mental energy or spiritual energy, that is not fixed by physics. So if substance dualism is true then it seems that one of the most fundamental laws of physics, the law of conservation, must be false. Some substance dualists have attempted to cope with this problem by claiming that for each infusion of spiritual energy, there is a diminution of physical energy, thus preserving a constant amount of energy in the universe. Others have said that the mind rearranges the distribution of energy in the universe without adding to it or subtracting from it. Eccles says that the mind can affect the body by altering the probability of neuronal events without any energy input, and that quantum physics enables us to see how this can be done: “The hypothesis of mind-brain interaction is that mental events act by a quantal probability field to alter the probability of emission of vesicles from presynaptic vesicular grids.”3 There is something ad hoc about these maneuvers, in the sense that the authors are convinced in advance of the truth of dualism and are trying to find some way, any way, that will make dualism consistent with physics.