I think the biggest failure in your reasoning is that we are arguing a black-and-white point here. This is most certainly not the case. There are many shades of grey as to the opinion of what caused Whitman to do what he did.
Since I chose to reply to your earlier post, you seem to be under the impression that I don't agree with everything you said, and that is just not the case. The only point you made that I take issue to is being able to call Whitman "a perfectly normal man". I don't dispute any of your claims that the tumor *may* have played a role in his violent impulses, and the Wikipedia article agrees with this assessment too. Furthermore, I would doubt any doctor in 1966 would be able to state as definitive fact whether or not the tumor played a role in his actions. It seems to me that the Connally Commission's purpose was to "right the wrong" of the previous medical examiner stating that there was no way the tumor did play a role. A responsible scientist would have to accept that we just don't know enough about the brain, or at least we didn't in 1966, and be forced to state their opinion in uncertain terms, which is precisely what the Connally Commission did; Wikipedia states that the tumor "conceivably could have had an influence on Whitman's actions."
The definition of a "perfectly normal man" varies from region to region, and changes over time, as Zynder points out. I assert that Whitman was not a "perfectly normal man", at least not by the standards of my region in this time period. I didn't grow up in America, and I wasn't subjected to the "gun culture" that seems to come with being an American. But again, in that Wikipedia article, Whitman's father makes the following statement:
His father said of him: "Charlie could plug (shoot) the eye out of a squirrel by the time he was sixteen."
In my region, this would be considered an early exposure to violence. I believe that if you're taught to use a gun at a young age, you shouldn't be taking the lives of innocent animals unless you intend to eat them for survival. Call me a peace lovin' hippie if you will, but this act demonstrates a lack of empathy for other living beings, and that, I would classify as not "normal".
But again, I must stress that this could be considered normal to someone living in another region, who perhaps grew up in America, in the "gun culture". The definition for a "normal" person is subjective.
On a side note, I have seen many of your posts on /. and quite often they are very informative and insightful. But I think a lot of people take issue with the way you refute their counterpoints by putting words in our mouths. For instance, in your reply to Zynder, you state:
... with the GP. He feels threatened by the idea that this sort of thing could happen to anyone and by anyone, I mean him.
I certainly do not feel threatened, and nowhere in my previous post did I even allude to that. Please don't put words in my mouth.
Further to that point, I certainly do believe it is entirely possible that a brain condition could strike anyone at any time and cause them to do very irrational things, like Whitman here. I just think your Whitman example is of someone who was predisposed to violence, and his predisposal to violence *may* have played a role in his actions, too.
That's great. You found one medical expert who agrees with you. Bravo, good for you. But to make a statement like this just shows a childish approach to the argument and paints it as black-and-white. Surely you can see that there are shades of grey to this argument...?