The more we find out about how the brain works, the less room there seems to be for personal choice and responsibility
I'm inclined to dismiss this quote on the grounds of bias. Allow me to explain why. We know almost nothing about how the brain works from a causal point of view. For example let's talk about how we have started mapping areas of the brain. They hook a person up to a device measuring brain activity, then they trigger certain emotions in that person or make him perform certain tasks. The areas with high brain activity are then obviously correlate to corresponding emotion/thought/task. However. We do not know how it works. Does the area become active due to the emotion or is it the other way around? What amount of control can free will have over that process? Can our free will trigger another process that counters it (if we would desire so)? Now I understand that for an atheist or an agnostic it might be easier to assume that the physiological process in the brain triggers the corresponding "feeling". However such an assumption would be biased by the belief that there is no soul, and hence there can be no free will. Since without a soul, the brain is nothing more then a set of physical actions and reactions. But the truth is we simply know to little to make such an assumption or to answer any of those earlier posed questions. Personally I'd say there's still plenty of room for free will.
In 2003, the Archives of Neurology carried a startling clinical report. A middle aged man with no history of misdemeanor began to stash child pornography and sexually molest his 8-year-old stepdaughter. Placed in the court system, his sexual behavior became increasingly compulsive. Eventually, after repeatedly complaining of headaches and vertigo, he was sent for a brain scan that revealed a large but benign tumor in the frontal area of his brain invading the septum and hypothalamus - regions known to science to regulate sexual behavior. After removal of the tumour, his sexual interests returned to normal. Months later, his sexual focus on young girls rekindled, and a new scan revealed that bits of the tissue missed in surgery had grown into a sizeable tumour. Surgery once again restored his behavioural profile to "normal".
In this specific case it is indeed very likely that his unnatural behavior was cause to the malfunctioning due to the tumor, and that this made it extremely difficult for this person to fight certain urges. However you have to realize that this is a exception and the majority of child offenders do not have such a tumor and do seem to be acting on their free will.
I'd like to point out different neuro-psychological researches who seem to point out that emotions can be addicting. Like the work of Jim Pfaus that illustrates how lustful sex will trigger an increase in the levels of serotonin, oxytocin and vasopressin. He further suggests these induce a state similar to the one created by taking opiates. Now this is very interesting because as we all know a person addicted to opiates might feel that he has no choice and that he simply must take his drugs to go on in a strict causal way. However the thousands of courage people who have fought their addiction cold turkey -and won the battle- have proven that this addiction -just like any other addiction- can be overcome by nothing more then free will. So that suggests the same is true for emotions and the urges that they create.
This case renders concrete the issue of free will. Did the man have free will? Was he responsible for his behaviour? Can a tumour usurp ones free will?
Well like I said, in this specific case it might be very likely that his free will was undermined by this tumor. But I would be extremely careful in extrapolating this to the minds of the general population and to assume that there is little or no free will for mankind; since this seems to be an exceptional case.
In non-human mammals, the density of peptide binding sites in the brain predicts whether a species is monogamous or polygamous. Male prairie voles with lots of vasopressin binding sites are monogamous while montane voles, with few are promiscuous. What determines the binding sites? Genes. Granting the effects of cultural complexity, something similar probably holds for humans too.
Yes, well it seems two points need to be raised here. The first is: in these animals it seems that the levels of these enzymes is set by specie. Certain species have high levels by default where others have low by nature. But nobody here ever suggested that animals have free will.
The second point, in human beings it seems that certain people have high levels while other have low levels of this enzyme. So apparently this is not simply determined by default for our specie as it is with animals. Which leaves me thinking there are two possibilities:
1. The levels are created by our free will, they are not a determent factor but a result. So it is a mechanism for the mind to control the body. Just as the levels of this enzyme in animals is determined by divine will (which also matches up with religion).
2. A more atheistic view: it's a mechanism for the body to control the mind and it's determined by luck of the draw.
Mind over matter or matter over mind? I think for now, in the absence of further evidence that we will be forced to "agree to disagree".