When you believe without sufficient evidence, you get results that are inconsistent and unreliable. Note how many different religions there are, and how many different denominations and interpretations of various "holy books" and texts. When you can verify things through evidence, you bring the various interpretations and hypotheses closer and closer together. Religion cannot do that, since the "evidence" is usually personal and subjective and nearly always unverifiable.
"Well, evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts don't go away when scientists debate rival theories to explain them. Einstein's theory of gravitation replaced Newton's in this century, but apples didn't suspend themselves in midair, pending the outcome. And humans evolved from ape- like ancestors whether they did so by Darwin's proposed mechanism or by some other yet to be discovered."
-Stephen Jay Gould
-Stephen Jay Gould
