[MarkPNeyer]

believing in something to be the truth, no matter how much 'convincing evidence' there is to support that conclusion, isn't really a scientific princple. skepticism, on the other hand, most certainly is.

science isn't about believing in anything to be the truth; it's about constructing analytical models that make accurate predictions while consistently exercising skepticism about the ability of any model to do so.

[hugh3]

Yes, the English language really lacks the vast suite of words we need in order to express our degrees of certainty about things. Words such as "know", "believe", "think" and "suspect" don't express these things properly, but we have to make do with what we have.

I don't think that "believe" is a particularly bad word for the relationship of a rational person to a fairly well established fact, though. I believe, for instance, that the Earth has an iron-nickel core. I fully acknowledge the possibility that it might not, and am fully ready to change that belief based on new evidence, but I think it's fairly well established and I am willing to act as if it were true.