This is a stimulating read. Free will, Harris asserts, is illusory.
It is an undeniable truth that genetics, upbringing and our social and cultural environment impact on free will to a greater extent than we would like to think. Less convincing though, is the emphasis on mysterious processes by which thoughts just "pop up" into the conscious mind, "as though sprung from the void." In fact, the word "mysterious" pops up with surprising frequency.
While I agree that our free will is very limited for the reasons given, there seems to be some confusion concerning the relationship between the conscious and unconscious mind. "Thoughts and intentions simply arise in the mind," Harris comments, ecouraging us to believe that these are products of a mysterious independent agent acting solely in its own, incomprehensible interests, and over which we have no control. "...you might observe that you no more decide the next thought you think than the next thought I write."
Only up to a point. While it is true that thoughts and intentions do enter the conscious mind unbidden, it's surely a two-way street. Internal factors, genetics, personal circumstances and outside influences may all impinge upon our consciousness, but by the same token, there is no reason why our own consciousness cannot also feed into and influence activity in the subconscious brain.
The English composer Edward Elgar famously said, "There is music in the air, music all around us, the world is full of it and you simply take what you require." Yet I will never snatch a new symphony out of the air. The truth is, Elgar chose to spend his whole life immersed in the language of music. That choice profoundly influenced the emergent properties of his subconscious mind, resulting in the creation of his original sound world.
The synergy between the conscious and the unconscious mind may remain elusive. The range of choices available to us are circumscribed and much is beyond our control - but not all.