h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Why has "atheist" become the label of choice these days -- We are defining ourselves in terms of something that we say does not exist! Why do we say it does not exist? Not just because of the dispute between evolution and creationism, but rather, thanks to the entire scientific arena, including the basic scientific method with its logical, rational thinking.
Logic not only leads us away from a "god" theory, but also away from "belief" or "faith" in general. Once we assert ourselves outside the realm of the "god-head" then a rational, non-woolly ethics might be visible. Check out Ayn Rand's Atlas Shrugged for an in-depth and challenging view of a non-belief-based ethics.

Why was it selected? Theists liked it as a way of insulting us--you'd have to be crazy to be without their god. The word becamse so common (and misdefined) that it has come intcommon usage whether we like it or not.