Do unto others

Remember, my son, that these are God's kingdoms, God who gives and takes away at his leisure... Be just to all men, equally to the poor and the rich, for injustice is the road to ruin; at the same time be gentle and merciful with those who are dependent upon you, for they are all creatures of God. Trust government of the provinces to wise, experienced men and punish without pity those ministers who oppress the people. Treat soldiers with gentle firmness so that they remain the defenders of the state and not its destroyers. Encourage and protect the cultivators, for it is they who provide us with our sustenance.... Never cease to merit the affection of your people; in their good will is the security of the state, in their anger there is anger, and in their hatred certain ruin. And rule so that the people bless you, so that they live happily in the shadow of your protection; for in that is the glory and joy of a king.

Abdur Rahman I, advising his son Hisham, at the declaration of royal succession of the kingdom of Al andalus (Arab Southern Spain) in 787 C.E.
(Source: "The End of Days", Erna Paris, http://www.ernaparis.com/works/enddays.htm)

It is a common claim among North American Christians, and likely other religious groups, that without Jesus, there is no point in being good, and no frame of reference for morals. As King Abdur Rahman's admonitions to his son clearly show, this is not a uniquely christian view. In fact,

there is near unanimity of opinion among almost all religions, ethical systems and philosophies that each person should treat others in a decent manner. Almost all of these groups have passages in their holy texts, or writings of their leaders, which promote this Ethic of Reciprocity. The most commonly known version in North America is the Golden Rule of Christianity. It is often expressed as "Do onto others as you would wish them do onto you."

(from: http://www.religioustolerance.org/reciproc.htm)

Any behaviour will only occur in a population if that behaviour confers survival value. Let´s review some conclusions from previous posts. From Dogs Are People Too, recall that the only big difference between animals and people is that we develop technology. Some technology is mental (belief in sprits or gods, culture, not eating pork, belief in the succession of the seasons), and some is physically instantiated (flint cutting tools, hammers, screwdrivers) From Principle: Survival of the Fittest Answer: we can say that the system which generates the most changes in technology (right or wrong), and allows robust and objective valuation, will be the system which advances most quickly, regardless of the problem domain. This amounts to saying that evolution works on people's culture.

In any ecosystem, the fiercest competition individuals of most species have to contend with comes from other individuals in the same species because they tend to occupy the same niche. Humans compete with each other by building bigger groups, held together by better thought technology (a better sete of memes), and physical technology (better tools.) in order to enhance the individuals' and the ability to feed themselves and have children (metabolism and reproduction.) Society arises as a competition strategy used by individuals within the species.

So if building a circle of allies is unarguably good, then what behaviours will that select for in human individuals? Well, there is a lot of early game theoretic results on iterated prisoner's dilemmas. In a prisoner's dillema, there is a payoff table:

PlayerB PlayerA

cooperate

defect

cooperate
1
2


defect
2
0



In each round of play, each player can choose to cooperate or defect. You don't know the number of rounds of play will be played. Computer algorithms were written to play the roles of A and B in this game. Tournaments were run, and for thirty years, a very simple strategy "Tit for tat" was the champion. The Tit for tat strategy can be simply summarized: cooperate. If the other guy defects, then defect on the following turn, if he cooperates, then go back to cooperating. The "tit for tat" strategy remained the champion for twenty years until just recently. Significantly, the strategy that defeated tit for tat was not an individual strategy at all, but one that used multiple types of players, some of whom altruistically sacrifice themselves for the good of the group. Only a culture can defeat an individual which excercises the golden rule.

Based on the success of tit for tat, I'll claim that for most individuals, the meme to be honest (so that communications will be simplest for others to understand, and therefore most effective) and "do unto others as you would have done unto you", is an evolutionarily stable and successful strategy, which should rapidly permeate any human population.

• Prisoner's Dilemma, William Poundstone, Doubleday 1992 ( A biography of John Von Neumann, with a lot of introductory material about Game Theory) ISBN 0-385-41580-X
• http://www.wired.com/news/culture/0,1284,65317,00.html -- 20th anniversary Prisoners dilemma tournament. Where the team strategy defeated tit for tat.