[kosta50]

I think part of this can be boiled down into selfishness. You're, I believe, saying that even if we don't behave selfishly, we're behaving selfishly because we want to not behave selfishly

It boils down to this: organism doesn't like to be hurt, pained, killed. Why? I don't know. That's how organisms behave. That's what humans verbalize. Perhaps it's an atavistic genetic trait that serves no other purpose but to preserve the species, for whatever reason. But that's how it is. It's selfish to the bone.

[D-fendr]

It boils down to this: organism doesn't like to be hurt, pained, killed.

Of course.

Perhaps it's an atavistic genetic trait that serves no other purpose but to preserve the species.

A logical assumption. However, now that you know that, you, conscious beings, humans, can overrule it, as you can choose not to eat when you're hungry, etc.