The debate about free will rages on and on, it always will, with some saying it would violate causality and the laws of physics if it were anything but an illusion, others pointing out that it is “god-given” and so must exist(!) and yet others pointing out that so much of the brain’s activity takes place below the radar of consciousness that free will is nothing but a retrospective perception of choice.
However, says Roy F. Baumeister in Slate:
There is no need to insist that free will is some kind of magical violation of causality. Free will is just another kind of cause. The causal process by which a person decides whether to marry is simply different from the processes that cause balls to roll downhill, ice to melt in the hot sun, a magnet to attract nails, or a stock price to rise and fall.