Say you can detect my body preparing to move before I’m conscious of my decision to move it, and you take it to prove that I have no free choice. If you’re right, you should be able to tell me when I was going to move without affecting the outcome. If my consciousness is not a cause of the what happens, nothing should change by making me conscious of what will happen.
So how about we run that experiment. Hook a bunch of persons who are convinced that they have free choice* up to an apparatus and tell them we’ll hit a light every time we know they will move. I predict the persons can give you any set of compliance/non-compliance ratios you want. And what would that tell us?
Notice that this is different from Libet’s “free-won’t” experiment, because there is nothing in it that says you have to not move when the light says you will. If you want a compliance/ non-compliance rate of .5, the guy you hook up can ask for 15 trials and comply on five. You could even ask for a total compliance ratio – but what would it mean to get it?
*We have to pick these sorts of people because otherwise our peers could critique any positive results by saying that the participants chose to give us the results we were looking for out of solidarity with us to prove free choice is a sham. Oh wait…