Now Freeman Dyson (yes that Freeman Dyson) and William Press have discovered that tit-for-tat is just a special case of a strategy called Zero Determinant or ZD. Using a ZD strategy the player can ensure that they receive a fixed percentage of their opponents jail time no matter what they play. In tit-for-tat the percentage is 50% but the ZD player can set this at 20% or 10% so always doing better than their opponent no matter what strategy they play.
If ZD is so good why doesn’t it occur in nature? The answer is that it isn’t evolutionary stable because when two ZD players meet they do worse than ZD against any other strategy and hence when there are too many ZD players in a population it becomes a disadvantage.
One possible solution is to recognize other smart ZD players and avoid them seeking out the dumb evolutionary players instead. Could this be why intelligence evolved?
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