Learning to play nice with other people

In today’s competitive landscape, where it seems everyone is looking out for themselves, it raises the question: how can cooperation possibly develop?

From the realms of evolutionary biology to the intricacies of international relations, game theory provides a framework to analyze various situations. Each game presents players with possible strategies and potential outcomes, known as payoffs, which can be either advantageous or detrimental. Some games are defined as “zero-sum,” wherein one participant’s gain equates to another’s loss; others defy that classification.

The prominent prisoner’s dilemma, which is not a zero-sum game, sheds light on this issue. It revolves around two criminals detained in isolated cells, unable to confer with one another.

While insufficient evidence limits their conviction for the main charge, they can still be prosecuted for a lesser offense. Both face a simultaneous proposition: betray the other to gain freedom while the other receives a three-year sentence. Conversely, should they both decide to betray one another, they would each endure two years behind bars. If both remain silent, they each receive one year on the minor charge.

The players’ results can be articulated in terms of years in prison. If both choose silence, their payoff is -1. Should player A betray player B, A earns 0 while B serves -3. Mutual betrayal leads to -2 for both. What strategies might optimize each player’s outcome?

Occasionally, a player adopts a strategy that serves as the optimal response to their opponent’s actions. This is termed a Nash equilibrium, where both participants select the best option for themselves, yielding optimal outcomes.

The predicament lies in the interactions of their choices, particularly when uncertainty about the other’s strategy looms. If you plan to maintain silence and your counterpart has the same intention, you’ll benefit by betraying. Conversely, if your opponent opts to betray, you’d be better off doing the same. Ultimately, the favorable choice appears to be betrayal. This reasoning holds for both players, leading to mutual betrayal and a collective outcome of -4.

Should both players trust one another and opt for silence, their joint payoff remains -2. This paradox, where a self-serving mindset leads to a more unfavorable result compared to cooperation, suggests a pathway for cooperation to arise.

A notable experiment in the 1980s observed 62 computer programs engaging in 200 rounds of the prisoner’s dilemma. Crucially, these programs could base their moves on their opponent’s previous actions. Strategies favoring self-interest typically yielded poorer results than those inclined toward cooperation. The successful strategies refrained from initial betrayal but retaliated if faced with an opponent’s betrayal, with the added feature of demonstrating forgiveness by returning to silent cooperation once their opponent ceased deceitful actions.

Therefore, while traditional game theory might pave the way toward adverse outcomes, it illustrates that a modicum of kindness can transcend this. Approach interactions with goodwill, but remain vigilant not to be taken advantage of. You can lean on the principles of game theory for support.

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