Having come at the issue from the other end (strict, literal fundie Christian) I can say that I am as convinced in my atheism as I once was in my theism. The difference being that my conviction as a theist was shaken as I continued to test it. Since I became an atheist, I really haven't seen anything that I hadn't already heard or used to try and support my theistic beliefs. Perhaps the most compelling being that a large part of theism (especially these days, IMO) consists of finding ways around the fact that god just won't reveal himself. I went through that phase in my life, and in the end it's very insensible and unsatisfying. I felt like Yahweh's secretary, telling people "he's been in a meeting since 33AD, and he'll be out in just a minute" for some 30 years.
"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
