According to Websters, fundamentalism is: "a movement or attitude stressing strict and literal adherence to a set of basic principles."

The definition lacks most of the connotations our modern media applies to it today.

Utaka, everybody makes decisions every day based on beliefs. I believe that if I get in my car it will start and I can go to work. Maybe my car's broken. Maybe I'll die on the way to work. I believe it will start and that I won't die on the way, lacking any evidence. I suppose I'm a nutter.

Tyranor, you're adhering rigidly to the idea that fundamentalists are stupid, thus filing yourself into your own definition of fundamentalism (which by the way is wrong). You're actually refusing to see in anything other than black and white (fundamentalists are stupid and there's no way around it) even as you condemn others for the very same thing you're guilty of. And because I'm a grammar Nazi, "Thus, is stupid" is a sentence fragment.

Stabdriver, though I agree with the second half, I'm not really sure how anything you said is relevant to the discussion at hand. In regards to the first half, if the word is synonymous its interchangeable; I wouldn't drive down the road and yell "HEY BUDDY! WHAT ARE YOU, A FUNDAMENTALIST!?" if somebody cuts me off. I also wouldn't say that somebody is a fundamentalist if they got a really easy question wrong in class. Clearly the words are not synonymous.

If I drive without ever breaking the speed limit and generally never break the traffic laws because they just shouldn't be broken, that makes me a Fundamentalist - I'm rigidly adhering to a strict set of rules. That doesn't make me stupid, even if it might make me really annoying to all the other drivers on the road.