Atheism is not a religion. It's the lack of one. (A-), meaning not or without, and (the-), meaning god, and -ism, meaning belief. So the belief of being without god, literally.
Atheism is not a code, nor is it a set of morals. Each person has their own philosophy, their own morals and whatnot. Atheism is merely the belief that no higher power exists.
You cannot take one atheists beliefs and apply them to the entire crowd, or even another atheist. They could be radically different.
I'm not to well versed in how to explain all this, though, but I'm basically saying that Atheism is not a belief system, not all atheists have the same beliefs and morals, and atheism is merely a disbelief in God.
Other than that, you'll have to take it up with each individual person to see what they believe in. I'll be glad to share my philosophy here, if you want it.
EDIT: I said "good" atheists. What I meant was someone that has morals and ethics and is a a generally good person. Even though the concepts of good and evil are subjective, we all have a good sense of what a "good" person is.
"It's better to die on your feet than to live on your knees"
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