Atheist moral code

[Esquilax]

It is entirely to each individual atheist to decide on their moral code.

Basically, moral relativism.

Only insofar as, say, fans of Metallica, or owners of a certain brand of refrigerator, could also be accused of moral relativism: like those two issues, atheism is a position on a single concept, not an overarching framework around which one builds their views. If you wouldn't say that people who like the Avengers are moral relativists because of the diversity of their moral views, you can't do the same to atheism.

And from where does the conscience come? Survival of the fittest hardly qualifies as a moral principle.

Our survival niche is community and group building, and an excellent way to ensure that those groups remain cohesive despite being diverse, is a sense of empathy, the conscience. Those of us who can consider moral propositions with greater complexity, who can imagine ourselves in the shoes of others, have a better chance of surviving than those that do not, within the context of the human species. It bears mentioning that "survival of the fittest" doesn't just mean strongest; it's a context sensitive phrase, where "fittest" means different things depending on the survival niches of the organism you're applying the phrase to. Fittest, with regards to humans, means those of us better able to leverage our group dynamics, which our conscience has developed to limit disruptions to.

Confirmation bias.

How so? Just naming a fallacy isn't a magic spell, you know. You need to go into a bit of detail.

Here is an interesting thought problem: Assume that humans and Neanderthals co-existed for a period of time, which I think has been shown to be the case. Here we have two sentient species each engaged in their own battle for their own survival. Does one or both have moral responsibilities to the other? What if the other species is entirely different, like the Formics in Ender’s Game?

I'm actually really glad you mentioned the Formics, because that's a really good example of how I would answer this question. Spoilers for Ender's Game, here.

At the end of the novel- I haven't seen the movie- we hear the Formic queen's side of the story; the Formics are hive-minded, and killing individual drones is akin to clipping a hangnail, to them. They, mistakenly, thought that they share this property with humans, leading them to kill human beings because they didn't see a problem with it from their perspective. When they found out that humans work differently to them, they stopped killing humans and withdrew, actually performing a type of ritualized suicide as penance for their mistakes.

Although I stop short at the ritual suicide part, I think this is a good example of how radically different species should approach each other: the Formics considered the morality of how they interacted with humans based on the context of how humans operated, and were able to make a moral choice that applies to humans but not to Formics. This kind of consideration is ideal; you observe the realities of how the other species lives, and construct your moral considerations regarding them based on that.