How the world works
Robert Axelrod
Reciprocity
Robert Axelrod (United States · born 1943) — Reciprocity.
What actually happened?
What he was actually trying to solve was nuclear war. Born in 1943, a mathematics degree from Chicago and a doctorate in political science from Yale, he kept returning to the question of his era: two states aimed at each other, trusting nothing, unable to fire, and somehow not fighting. Others worked on the negotiating table, on deterrence, on morality. He took a stranger route. He compressed the whole thing into a game with two moves, cooperate or defect, played over and over, and then refused to solve it himself. He posted the problem and asked the world to send programs.
He ran a tournament instead of proving a theorem
The usual answer to which strategy is best is a model and a proof. He published the rules, asked researchers to submit their best rule as code, played every pair and let the totals rank them. The answer was played out, not thought up.
Rather than arguing in the meeting over which plan is better, run both for a month and read the numbers.
The shortest entry won
TIT FOR TAT is four lines: cooperate on the first move, then copy the other side's last one. The second tournament drew sixty-two programs whose authors all knew it had won and knew its weaknesses. None of them beat it.
The rule everyone can read, and everyone can predict, usually outlasts the one with something hidden in it.
The dividing line was moving first
No program near the top ever defected first. They let every chance to take advantage go past and still scored highest. The ones that took those chances collected early and spent the rest of the tournament against opponents they had made.
The two points squeezed out of this contract are usually drawn in advance from the next one.
Cooperation needs no friendship, only a next time
He pushes the claim to its floor. In the trenches of the Western Front the two sides had never met, were ordered to shoot each other and had no authority between them, and a tacit truce grew anyway, because the same men faced each other daily.
Two firms in the same building settle a dispute far more easily than two on different continents.
How do I use it today?
To get something honoured, stop auditing the other person's character and count the rounds instead. Turn a single payment into monthly ones, split delivery into three stages, put the two of you somewhere you both have to keep showing up - once tomorrow holds the same two people, their arithmetic changes on its own. Then fix your own rule of response: never move first; if you are genuinely crossed, answer once, and only once; the moment they cooperate again, cooperate on your very next move, with no arrears and no ledger. Half of that rule on its own is either an invitation or a permanent feud.
Deep read
Read alongside
Further
Lines to keep
A promise holds because of tomorrow's meeting, not his character.