If we fast-forward to your conclusion, viz. “I think we’ll learn a lot more about how brains work and, perhaps, about how minds work the next 50 years. But it may turn out that the question of free will is an unanswerable question,” we are in fundamental agreement. This is either completely consistent with what I said or is identical to what I was saying. However, my fear is that certain members of the scientific tribe will mistake a description of a process for an explanation of a process.
On Eastern spirituality, I think the relaxation that leads to dissolution of the ego and its melding into universal consciousness, or divinity, is motivated by a desire to escape rather than by some fundamental intuition about reality. What one is escaping is incarnation and the desires which incarnation requires.
Most generally, we are caught in a vicious circle, each of us. You think that the experience of subjectivity can be analyzed into physical components. I think that this analysis does violence to the subjective experience itself, that such an “explanation” is a priori impossible. My contention is that the brain gives us access to something like an idea of subjectivity that constitutes an a priori realm comparable to the realm of the laws of arithmetic, which I take to be independent of human neurophysiology and evolution. The fact that the base system of numbers can be altered doesn’t change the fact that arithmetic is independent of physical reality, would be true in any possible world, real or imagined. Stated metaphorically, our subjectivity proves that God counts (the alternative being that there is only one thing and that counting amounts to a violation of reality, or has a provisional truth that belongs to a world of appearance).
Now, the problem is that “your side” will eventually resort to experiments which, it will be asserted, prove that subjectivity is “just” some complex neurological process, and the experiment will consist in isolating the effects of stimuli on the brain, and so on, but the so-called proof is impossible, in principle. That is, one could have two completely isomorphic geometrical maps, visual maps, or mathematical maps of two brains, or of an actual brain and a virtual brain, but what are these maps going to tell us about the subjective experience in the actual brain? There is in principle, a priori, no way of getting from the map to the experience. This is what you are at pains to deny, the difference in kind between the physical-mathematical description of the experience and the experience itself. This is why I said before that I agree that it will be very difficult to distinguish an act of free will from a determined physical act, but since we know in advance that this will be difficult, we had better take pains to make the distinction now.
My contention is that the experience of willing cannot be an illusion. What difference does it make if 99.5% of all acts that are experienced by humans as acts of free will are preceded by one nanosecond by a particular physical process? I’ll grant that this is the case, I assume that it is the case, but so what? Maybe the process appears to differ from case to case, maybe it doesn’t, maybe we can’t find the level of generality that explains the vast majority of cases according to one simple or complex process, all of that is moot. We can’t get from the physical to the psychological, in principle, this is my contention. The whole enterprise consists in what the philosophers call a “metabasis eis allo genos,” a “crossing over into another kind of thing.” You say that we have no way of distinguishing between the map and the experience, while I say that we can and do know in advance that the two things are not the same. Nothing I have said is inconsistent with the idea that acts of willing can be altered in their nature or effects by doing something to the brain. To the contrary, I assume this to be the case. I just don’t see how this changes the problem. Perhaps my acts of will are affected by whether a butterfly alights on a particular flower in Brazil, or by what some intelligence in another galaxy is thinking or doing. Does any of this really alter the fact that, in the end, there is an “I” who chooses to do, or to refrain from doing, this or that? I can see that one can, and probably will, pile up contributory “causes” in the physical realm ad infinitum, but the actual act of willing will remain there, impervious and impregnable.
What I predict will occur in the realm of scientific psychology are therefore two scientific processes that are themselves at odds with one another and will never be reconciled. On the one hand, there will be physical analysis at the micro level, and various mental acts will be associated with various predecessor neurophysiological processes. Simultaneously, at a macro level other scientists will argue that it is incorrect to isolate the subject from this or that influence, influences which might extend to other galaxies and other possible worlds. But in a parallel world to both of these movements in physical science will be the philosophical investigation of inwardness and the laws of subjectivity that belong to themselves, unless that investigation is destroyed by the hubris of physical science. Basically, either the mental can be reduced to the physical or it cannot, either there is something called mind that is not merely physical, or there is not.
My contention is that an honest investigation of subjective experience proves that there is a mental realm which can govern the physical, or that mind governs body. But supposing the contrary, that mind is just a physical process, what scientific experiment can be imagined that would prove that mind is just a physical process and that would not involve simply assuming what was to be demonstrated?