A quick summary explaining why I reject free will. Free will is the idea that we can change the future. This is a paradox. If we did succeed in changing the future, then that was never going to be the future. We never witnessed the future changing, we only saw the future come in a way that differs from our prediction of it given we didn’t take the action we took.
What gives rise to the illusion? A poor understanding of causal relationships. Suppose we have a blue wall in front of us and a can of red paint. We can cause the wall to become red by painting it. We changed the wall.
We try to apply this sort of reasoning about the future even though we cannot see the future. We look at the future and see it as us not drinking a can of coke. So we cause ourselves to drink the can (by thought processes). Therefore we changed the future? No, we did NOT. We only changed our estimation of what that particular point in time would look like. Instead of admitting that our view of the future where we weren’t drinking coke was false and inaccurate, we instead say “we cause it to change with free will so we weren’t wrong” even though all the evidence proves that the model of the future we had was wrong.