Traps of Our Own Design
The prisoner’s dilemma distilled the tension between selfishness and co-operation into a potent form, making it emblematic of the risk of nuclear destruction and much more besides.
Capital Thinking • Issue #535 • View online
Once upon a time, a pianist was arrested by the secret police and accused of spying. He was carrying sheets of paper covered with a mysterious code.
Despite protesting that it was merely the sheet music for Beethoven’s Moonlight sonata, the poor man was marched to the cells.
A couple of hours later, a sinister interrogator walked in. “You’d better tell us everything, comrade,” he announced with a thin smile. “We have caught your friend Beethoven. He is already talking.”
The Prisoner’s Dilemma at 70 – and What We Get Wrong About It
Tim Hartford | The Undercover Economist:
This sets up the most famous problem in game theory: the prisoner’s dilemma.
The interrogator explains that if one man confesses and the other does not, the talkative prisoner will go free and the other will do 25 years in a gulag.
If they both remain silent, they will each spend five years in prison. If they both confess, 20 years each.
The dilemma is clear enough: each would do better to confess, regardless of what the other does; yet collectively they could profit by sticking together.
The dilemma is now 70 years old — it was developed in a simple mathematical form in 1950 by mathematicians Merrill Flood and Melvin Dresher and wrapped in a story by Albert Tucker. (My own retelling owes a debt to economists Avinash Dixit and Barry Nalebuff.)
Dresher, Flood and Tucker worked at the Rand think-tank.
The prisoner’s dilemma distilled the tension between selfishness and co-operation into a potent form, making it emblematic of the risk of nuclear destruction and much more besides.
The dilemma received a second burst of attention in 1981, after the publication of “The Evolution of Cooperation” by political scientist Robert Axelrod and evolutionary biologist William Hamilton. Their article is not only the most cited in political science, but as popular as the next three works put together.
I hope readers will forgive my dredging up such a venerable idea, because it remains relevant, instructive, and widely misunderstood.
One common misunderstanding is that the problem is one of communication: if only the pianist and Beethoven could get together and agree a strategy, they’d figure out that they should stick together.
Not so.
Communication doesn’t solve anything.
The attraction of teaming up is obvious; so is the temptation to betray.
Those who believe talking helps much should watch Golden Balls, a game show based on a modified prisoner’s dilemma. What makes the show fun to watch is the emptiness of the promises contestants make to each other.
More problematic is the mistaken belief that the prisoner’s dilemma means we are doomed to selfish self-destruction.
Moral philosophers have tied themselves in knots trying to refute it, to show that it is somehow rational to collaborate in a one-shot prisoner’s dilemma.
It isn’t.
Fortunately, most human interaction is not a one-shot prisoner’s dilemma.
*Featured post photo by Damir Spanic on Unsplash