And I have 100 times as much certainty evil thugs, who are indeed mentally twisted, but who DO understand that they are evil, abuse the hell out of 'insanity'.
I know what you are trying to say but I think it is much more complex than that.
For ever one truly 'insane to the point of no free will' individual, there are at least a hundred 'violently twisted but still aware' thugs.
You can be perfectly aware of what you are doing and still not be doing it with a Free Will.
again.... mental illness is a behavioral disorder of the brain. Addiction to drugs being one of the more obvious behavioral disorders.
The brain is a complex organ. One of the most complex things in the known universe. The result of billions of years of evolution.
That brain responds to stimuli either internal or external.
If they are mentally "twisted" or mentally ill their brains are "malfunctioning". Responding inappropriately. They need help. Not jail actually. They are kind of trapped in a set of deterministic factors. Like a computer program stuck in a loop they cannot escape. It is a mere social convention to assign all the blame to the individual . This reflects a primitive understanding of the causes of human behavior.
But, what is malfunctioning...what is "normal"? How do we reprogram them to be "normal". And should we?? Can we? (yes we are soon getting to the point that we will be able to do just that) And what does that mean to their sense of identity. If we wipe their memories clean and reprogram them what are the ethical ramifications of being able to do that? And will that give them "free will"?
see...Eternal Sunshine of the Spotless Mind
Maybe they are not malfunctioning at all. Maybe they just evolved and arrived at the wrong time and in the wrong place. What appears to be evil in one situation or time is perfectively normal behavior in another. Because they are out of sync with society we call them evil and twisted.
An "evil thug" may under different circumstances in a different time be the perfect hunter or the perfect knight or the perfect soldier.
I think there are far far fewer humans who have as much Free Will as you think they do. Free Will has been debated for ages and we are not going to solve it here. In my limited experience I will tell you that it seems to me that there are a lot of people out there (even the intelligent ones)who don't really know why they do what they do.
Ask any kid why he did that terrible thing he is being punished for. He will most likely say, "I don't know." Because they don't or they don't want to know.
Nor do they always have the ability (or the training or whatever) to inhibit or override their own behavior and when they do it that is also the product of their own particular physiology, which is a consequence of their own unique developmental experiences, which occurred within a particular cultural environment, which was a reaction to a particular set of genes, which was the result of his parents interacting in another particular environment and another particular set of genes, who inherited their genetic traits from their parents, and so on and so forth...
And yet we blame the individual for reacting inappropriately to a particular set of stimuli because of his particular set of deterministic factors that he actually probably had very little control over.