A wonderful Monty Python sketch involves a hypnotist who "builds" public housing. A reporter asks a resident "how does it feel to live in the figment of someone else's imagination?" Paraphrasing, the resident responds "well, it was better than where we were living before."

Existentially speaking, I think that's an awesome insight, and speaks to the free will question. The human experience is all we have. We label a part of our experience "free will." Compared to what other human mental experience? Thoughts come to us that we don't seem to have any control over, or that we wonder why they happened.

Sometimes I think life is a movie we each watch. It seems plausible that what goes on in our heads is part of the movie --how could we really "prove" otherwise?

From a neuroscience perspective, our conscious mind takes in a myriad of inputs from parts of our minds we are not conscious of. That makes me disbelieve determinism. How could a neuroscientist ever determine the cause of a thought or a decision with so many colliding inputs? It seems as problematic as predicting wave function collapse prior to measurement. What's the difference between free will and the uncaused appearance of our thought?