Please note that what follows can be interpreted as criticism, but it's not intended as such. I found this article quite interesting, and for me, it was the starting point for a lot of different thoughts about game-theoretical approximations of morality. So what follows is a somewhat tangential addition to the article, and not a critique of it.<p>My problem is not with the "eigenmorality" concept, nor with the various takes on playing it out across consecutive Prisoner's Dilemma sessions. That aspect is extremely interesting. Rather, my problem is with the Prisoner's Dilemma as a valid ground on which to test something like morality.<p>The Prisoner's Dilemma is a foundational, theoretical framework for evaluating human behavior. And it's a wonderful, elegant framework. But it treats humans as emotionless agents, and the "punishment" as an abstract, theoretical, rationally navigable scenario. Place real human beings into the Prisoner's Dilemma, with real-world consequences, and you get all sorts of unexpected results. The Prisoner's Dilemma is notorious for holding up perfectly fine <i>in vitro</i>, but less so <i>in situ</i>. Cultural conditioning plays a <i>huge</i> role in how real people act in the game. So do emotions, and irrational heuristics like overemphasizing loss aversion. (Tversky and Kahneman's work has a lot to say about the latter.)<p>Using the Prisoner's Dilemma as a proving ground, I think you'd arrive at an abstract model of morality -- but you wouldn't capture how morality actually plays out with quasi-rational, emotional, circumstantially driven, human agents. And, philosophically speaking, that's where morality actually counts the most.