The brain is a massively parallel machine, with many parts performing the same function using different methods. It is like a democracy with many factions competing to determine the final, single outcome. There is no single “me”.
We are also highly influenced by our biology: genes and the delicate balance in the functioning of our brain. A man is much more likely than a woman to be in prison and a murderer. A gentle and well-liked man can suddenly become violent or a sexual maniac who cannot control himself - because of damage to the frontal lobe of his brain. We can, obviously, be easily influenced by alcohol, cocaine, other drugs, and the environment around us. For example, only a small number of men are actually in prison or are murderers, and the probability of doing so is heavily influenced by the way that they grow up.
These are all very fascinating and convincing. We may not be fully in control of ourselves - that I have to agree with. But then he suddenly claims that “all activity in the brain is driven by other activity in the brain,” ... “we can’t find the physical gap in which to slip free will.”
There is obviously a big jump from the solidly-backed-up “we may not be in complete control” to the yet-to-be-proven “we have no control at all.” The book makes a lot of convincing observations backed by solid research; then it suddenly slips in a conclusion with tremendous implications with a flimsy pretext. This is the result of either carelessness, or sneaky sleight-of-hand.
This is one of those many books that open with a bang but close with a whimper.