"Only someone miraculously innocent of history could believe that competition among ideas could result in the triumph of truth" John Gray
The interesting aspect of this OP is the fact the authors were criticized and eventually corrected where wrong. That is what science does, or is supposed to do, even if late to the game. Comments on certain aspects from personal knowledge:
If you live in a big city chances are there are the good sections and the not so good sections. You don't have to guess who mostly lives in the not so good sections, nor do you wonder at their ethnicity. Why. I can give reasons on all sides, but reasons are often ignored if the stereotype is strong enough. If I were to take the average joe around the various streets I bicycle, do you know what they would say? Guess. No need to say more.
Now guns. First I have read that guns were rare in colonial times. Given manufacturing then, that doesn't seem all that earth shaking. Gary Wills writes about that aspect in 'A Necessary Evil.' But can anyone of my generation remember all this hullabaloo about guns when they grew up? I remember nothing at all? So then something must have changed. Again the answer is kinda obvious but rarely spoken.
Comic books, movies, books, etc etc were always the cause of all sorts of things, one can find a so called scientist who claims anything, so this is hardly a reason to give up on science. We used to study the list of forbidden books and movies in church on Sunday just in case we had an opportunity to enjoy one. Boys will be....and we turned out alright.
As for 'The Authoritarian Personality' for those of us to whom the Holocaust changed how they viewed good and evil, Adorno's study was an attempt to understand. Personality does matter. Read Stanley Milgram or check out this video:
Philip Zimbardo: The psychology of evil | Video on TED.com
And if you read: [ame=http://www.amazon.com/Becoming-Evil-Ordinary-Genocide-Killing/dp/0195189493/ref=pd_cp_b_2]Amazon.com: Becoming Evil: How Ordinary People Commit Genocide and Mass Killing (9780195189490): James Waller: Books[/ame]
Gun laws. [ame=http://www.amazon.com/Gunfight-Battle-over-Right-America/dp/0393077411/ref=cm_cr_pr_sims_t]Amazon.com: Gunfight: The Battle over the Right to Bear Arms in America (9780393077414): Adam Winkler: Books[/ame]
Scientist noted in OP making up stuff.
http://www.nytimes.com/2013/04/28/magazine/diederik-stapels-audacious-academic-fraud.html
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