I think that creationists have an intense need to be sure that their view of the world is absolutely the truth. They don't seem to be able to deal with doubt very well. When I left Christianity it was a very hard time for me. I suddenly didn't have an absolute standard by which to judge morality, and that was very difficult for me. Probably the worst part of all was no longer knowing, for a fact, that no matter how bad things get, everything will come out alright in the end. Evil people actually can, and have, "gotten a way with it". Good people do suffer needlessly, and never get justice. It was pretty hard to bear at first.
As far as the evolutionist mind set, I don't think it is as easy to characterize, including, as it does, humanists and totalitarians, Christians and atheists, idealists and cynics. I was a devout fundamental Christian first, and then, despite everything, it was evidence and logic that convinced me that the theory of evolution was accurate. I don't feel that it met any needs of mine - in fact, as I said in my previous paragraph, since it led me to atheism it, at first anyway,
undermined all my needs that were being met.
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