http://ncse.com/evolution/education/definitions-fact-theory-law-scientific-work
Fact: In science, an observation that has been repeatedly confirmed and for all practical purposes is accepted as “true.” Truth in science, however, is never final and what is accepted as a fact today may be modified or even discarded tomorrow.
Theory: In science, a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.
Basically, a fact is an observation, while a theory is an explanation.
I can't possibly see how believing in what has been proven and not believing in what hasn't been proven leads someone to "have a grudge" against someone else who doesn't. I hold no grudges against theists, I just think they're being irrational.
(continued from above)
The validity of "theories" depends entirely on how substantiated they are. If new evidence arises that supports an alternative theory, then the alternative theory will be considered and may even be accepted if the evidence is strong enough. As such, people who accept the scientific method are entirely able to "change their beliefs", while those that don't tend to be more close-minded.
In school, we are encouraged to question what we are taught. If a teacher can't respond to questions appropriately, then they are a crappy teacher.
People who
think they've had near-death experiences mean next-to-nothing in terms of evidence, since they tend to reject other possibilities and assert things that can't be examined and/or proven.
In science, we call this "close-mindedness".
