I was looking at the-brights.net. They define a "bright" as "a person who has a naturalistic worldview". I was thinking that seemed a bit circular, when I had this epiphany: everything is "natural". If clear reproducible evidence of ghosts is discovered tomorrow then ghosts become part of a naturalistic world view. What makes me an atheist is not a list of things I do and do not believe, each of which could change with new evidence. The important thing is how we go about deciding what to believe. I'm a big fan of the scientific method. Now I just have to figure out why, how that works, and what to do when it doesn't apply so well.