"You forget we are social critters. We live in groups because we need cooperation among individuals to survive"
"They are out-competed very effectively by societies that promote co-operation"
You are still dealing in the area of self interest, not altruism or common good. The Carnegies, Rockefellers, Fords, Soros, Gates, Stalins, Pol Pots, China, North Korea, Iran, Saudi Arabia all use cooperation to suit their selfish ends but when necessary they, at heart, are ruthless self monopolists right out of the Ayn Rand school of the strong individualist survives because there is nothing greater than themselves or a transcendant being they must one day answer to.
How can you trust someone whose ethic is what he thinks is right at the time but might change in the next minute do to a changing circumstance? Who is to say that the looting actions in New Orleans during and after Katrina are not justfied by the ethic of the have-nots getting their "just" do? Certainly in those circumstances cooperation or "the Golden Rule" was suspended in the face of self interest.
How can I trust someone who only behaves because he is frightened of a God that I don't believe in? What if you guys get a crisis of faith?
I note the usual marxism from the creationist side in the rest of your response.
Principles, my friend. Principles. An ad-hoc, self-serving moral "code" is a contradiction in terms. Any moral system must be applied consistently every time in similar contexts. For example, if my code is to only deal with businesses that treat me fairly, openly praise the ones that go beyond that basic standard, and openly denounce the ones that fail to live up to it, then I must accept that others should be allowed to do the same WRT doing business with me.
Whatever rules I make up for myself that I think will give me an advantage in life, I must also allow other people to treat me in the same ways in their dealings with me.
That is only fair, and I contend that if you follow any self-interested principle consistently like that, you'll never end up acting in a manner that we would consider predatory or unfair.
You make a good point. Self-interest always prevails in man; it's his nature.
All men are either led by God for His purpose or they're not.