By dkl9, written 2025-163, revised 2025-163 (0 revisions)
After I tell you free will isn't real, you probably object with the standard complaint. How and why are we to hold people accountable for their sins, if they couldn't choose them?
Consider a tablet of soft clay. When made anew, smooth, a ball dropped on it could equally well roll any way. If you press a groove into the tablet, a ball dropped near the groove rolls into and then along it. To get balls to go to the right, you could press grooves into the tablet, slanted downward toward the right. It'd work better to tilt the tablet, or push around the whole mass of clay into a slant. Perhaps the tablet is fixed to the ground. Your tools and strength are limited. As you can only groove so much of the surface, some balls won't land in grooves, and instead roll the other way.
Balls rolling on clay are clearly deterministic. By analogy, human minds respond to incentives, despite that they're deterministic:
Credibly threaten to punish, and that threat will alter their brain, at tiny scales. Likewise promise to reward, and that promise alters their brain. Either way, such changes later affect what they do, along with the rest of their brain-state.
If such a tendency to process incentives to determine actions is exactly what you call "free will", then we trivially agree. In that case, I was just confused about what you meant by "free will". Usually people mean something else by "free will", something that assumes people act non-deterministically.
If people should do more good and less bad, promise and threaten them accordingly. This is useful insofar as incentives change what they do. Such changes happens insofar as actions are subject to what we call motivation, interest, and argument. That is, even if people didn't "really choose" what they do, it still makes sense to enforce morals.
You may argue further on whether people have free will. Please first understand that morality won't collapse if we find out free will is fake.