I can, for instance, reach for my cup of coffee or set it down, seemingly as I please. These are intentional actions, and I perform them. But if I look for what underlies these movements—motor neurons, muscle fibers, neurotransmitters—I can’t feel or see a thing. And how do I initiate this behavior? I haven’t a clue. In what sense, then, do I initiate it? That is difficult to say.
