I would just like to say that after a very short time your site has become a strong favourite of mine. I find it incredibly informative, inspiring, entertaining, and even addictive at times.
I agree completely with your point of view, and often wonder why such a logical perspective isn’t far more common. Even with the very limited knowledge that one like me possesses, I can’t help but see open-minded atheism (I refuse to name it weak atheism, which just sounds derogatory) as simple common sense.
Like you, however, I love a good debate.
I have no story to tell of turning from my faith (having been raised as a Christian in a very loose sense, and accepting atheism when I was about 8). Nor do I have any obvious questions for you, as I seem to agree with you entirely!
I apologise if you’ve replied to a similar question before, but I’m eagre to become involved in discussions due to my favour of your site. So:
Considering the apparent non-existence of deities and their consequential irrelevance to morality, where should the moral beliefs of an atheist stem from, and by what source or authority should they determine the correct way to behave?
I also dislike the term “weak atheism.” I prefer to call myself a “moral atheist,” and define that as a system of moral thought, derived from basic principles, that happens to include atheism. For me, having a well-developed philosophy and living by that philosophy is far more important that happening to not find arguments for the existence of deities convincing.
This leads me to your question.
I use a system of thinking I call The Two Questions. It involves subjecting any system of belief to a two-question test before accepting it as possibly valid. The two questions are “Does my philosophy contradict itself?” and “Would I condemn another for reasoning as I do?” If I answer “yes” to either question, then I know I’m on the wrong track. I believe most people would agree that their moral philosophy should be able to pass this test.
In addition to this system of thinking, I assume that people have self interest. I think that’s the only assumption you need in order to derive a basic morality. For example, is it okay to murder for fun? Well, if it’s okay for me to murder for fun then, if I want to pass the Two Questions test, I have to say it’s okay for others to murder for fun, which implies that I think it’s okay for them to murder me for fun. Well, self interest rules that out, so I must believe that murder is wrong.
A more complex personal philosophy can be built if you agree that most people have an innate moral sense. Religious people would likely say that this sense was instilled by God, but I think it just as easily could have evolved and/or been instilled by society. However, you have to be a bit careful when you rely on this sense to building a philosophy as it can vary from culture to culture (some people have a moral repulsion to women walking topless in public, for example, but this is clearly not a universal moral stand).
When you ask about an authority for determining correct behavior, I have to say that there is not one (or, at least, not one that is authoritative on this subject). You have to take care of yourself. This, however, does not mean that everything is relative and one person’s morality is just as good as another’s. Some things are clearly morally wrong for everyone.
Let me know if this answered your question. I can go into it in more detail, if you like. Also, I will be putting out a pre-publication copy of my new book on The Two Questions in October (if all goes well) for my readers to comment on before the final edition is published. I hope you will participate in the project!