It does randomly pop into your mind, though. We don't choose what thoughts arise. You can rationalize the thought once it does pop into your mind. So the thought pops up that you want a 2nd cup so you can think no, I already had 2 and that's enough or it will keep me awake at night. But the argument is none of those thoughts were actually selected, they just enter our consciousness.
Addiction is a perfect example of people taking action against their rationale. For example, people know smoking cigarettes is bad but they just can't kick the habit.
An example that clarifies it for me is attraction. When you see a beautiful woman there is no conscious thought about it. You simply have a reaction. Any thought can be described similarly, that our brains have responses to any stimuli.
BTW I find these arguments compelling but also find counterarguments from guys like Dennett compelling as well. I wouldn't argue to the death on this position but I find the idea that free will is an illusion aligns with my thinking on the issue and just makes a lot of sense. I also acknowledge why the idea is very hard to grapple with given how much people value free will and the extent we base so much of our society it.
I also find a lot of the anti-free will arguments compelling. As you say, people don’t choose the thoughts that pop into their minds, they don’t choose to be depressed or addicted... they certainly don’t choose which family, nation, or time period, to be born into, etc. Much less do we choose the laws of nature, forces of the universe or structures of consciousness itself!
But there is a gallous gap between saying that a LOT of our experience is beyond our free will and that we have NO free will. 99.99999% of our experience could lie outside or free will and we still HAVE free will.
And phenomenologically, doesn’t that make a lot more sense? Why and how do states of mind such as crippling indecision exist if we have no free will?
On a more pedestrian basis, it gets silly very quickly. If you walk into McDonalds are you telling me that you have absolutely no agency over whether you get a 12 piece McNugget or a McDouble with fries? And that there was no agency in choosing McDonalds over Buger King... or either over a salad??
I'm not sure, I read the book quite a while ago and only recall the main arguments at the moment.
Maybe I'm just not following your criticism here but why would he need to provide a philosophically convincing reason to rely on knowledge of neuroscience? It seems to me to be perfectly cogent to accept knowledge gathered via the scientific method if our understanding is well known. We know that folks who are unlucky enough to sustain brain damage have changes in thoughts, actions, loss of memory. It's really good evidence that what we think and do are directed by our brains (pretty uncontroversial).
Another example is people who experience depression and suicidal thoughts after a traumatic experience(s) (like war, death of a child, etc.). You would grant that these thoughts are not chosen or a result of our free will to be depressed right?
So, you are combining two points here. One is the free will thing, which I’ve already addressed (hopefully satisfactorily).
The other is the question of epistemology (Why do I need to provide a philosophical reason to accept the findings of neuroscience?)
The answer is you don’t need to provide a philosophical reason to accept the findings of neuroscience
in the field of neuroscience.
However, you absolutely DO need to present a philosophical argument if you want to convince a non-biased observer that the findings of neuroscience should be privileged as THE basic epistemology.
You either take questions of epistemology and metaphysics seriously or you do not. Sam Harris (from what I’ve seen) really doesn’t. He simply swaps out philosophy for neuroscience, much the same way Dawkins simply swaps out philosophy for biology. And they both figure their expertise in their respective fields should be a convincing enough explanation as to why.
This is (in my opinion) the basic bait and switch of all the “new aetheists.” They offer scientific answers to philosophical questions while (largely) ignoring the very philosophical complexities that make this untenable.
Once again: scientific answer to scientific question, no issue. But if you want to convince neutral observers to consider the entire existential experience in toto PURELY through a materialist lens and to disregard all other possibilities, you’ve got a lot of explaining/convincing to do.