My question is how do you decide that the conclusion you come to as to what's right or wrong is superior to anyone else's conclusion? edit: Or put another way what gives you that right?
Ah, now we're getting somewhere. The question is how do you decide that the conclusion you come to about what god to believe in is superior to anyone else's conclusion? Or put another way, what gives you the right to believe someone else is going to hell (or whatever outcome nonbelievers of your religion face)?
There are any number of ways, combined, that an atheist can come to a conclusion about what's right and wrong, and they may even feel that it's not necessarily superior to anyone else's, but seems to be what works best for
them--just as there are varying degrees of ecumenical cooperation among similar religions who nonetheless can argue endlessly about smaller differences.
And I'd suggest that the ways in which atheists come to conclusions about right and wrong, are similar to how religious people choose their religions.
--Observation of others' behavior, following role models, avoiding others' mistakes, discovering what motivates the behavior of people they admire
--Thinking to themselves about the logical outcome of different behavior, observing "how the world works" and trying to make sense of it, forming their own theories that they can defend against others' objections
--Responding to a lifetime of societal pressure, either praise for following cultural traditions or a lack of punishment for doing something that would be considered unethical/sacreligious in another culture.
--A gut feeling. "It just seems like the right thing to do." "I don't know how I know, but I know it's true." "When I first heard it, I knew from that moment...." One can get into neutransmitters, evolution, etc. to explain it, but subjectively that's how most people express that aspect of belief.
Human nature being what it is, once some combination of all those things set a person along a certain course, they may consciously have to change the way they feel about some things, but if their overall chosen course has too many illogical, indefensible, "just doesn't feel right" aspects, they'll probably pick a different course, rather than stick rigidly to their original choice.
As an exaggerated example, the average person who wants to convert to a religion that otherwise seems to fit, but requires them to quit smoking, will probably go to the effort of quitting smoking, even if they wouldn't otherwise. However, if it requires them to sacrifice their first-born, they'd probably say, "no thanks," and pick another religion. Same way, an atheist whose logic requires them to do no harm to any humans or animals might give up eating meat, but probably wouldn't stand by while a rabid dog attacks their child; instead they'd rethink their logic about circumstances when the rights of one creature do take precedence over another.
