Hilbe Christian, Röhl Torsten, Milinski Manfred
1] Evolutionary Theory Group, Max-Planck-Institute for Evolutionary Biology, August-Thienemann-Strasse 2, 24306 Plön, Germany [2] Program for Evolutionary Dynamics, Harvard University, One Brattle Square, Cambridge, Massachusetts 02138, USA.
Evolutionary Theory Group, Max-Planck-Institute for Evolutionary Biology, August-Thienemann-Strasse 2, 24306 Plön, Germany.
Nat Commun. 2014 May 29;5:3976. doi: 10.1038/ncomms4976.
Extortion is the practice of obtaining advantages through explicit forces and threats. Recently, it was demonstrated that even the repeated prisoner's dilemma, one of the key models to explain mutual cooperation, allows for implicit forms of extortion. According to the theory, extortioners demand and receive an excessive share of any surplus, which allows them to outperform any adapting co-player. To explore the performance of such strategies against humans, we have designed an economic experiment in which participants were matched either with an extortioner or with a generous co-player. Although extortioners succeeded against each of their human opponents, extortion resulted in lower payoffs than generosity. Human subjects showed a strong concern for fairness: they punished extortion by refusing to fully cooperate, thereby reducing their own, and even more so, the extortioner's gains. Thus, the prospects of extorting others in social relationships seem limited; in the long run, generosity is more profitable.
敲诈勒索是指通过明示的武力和威胁来获取利益的行为。最近有研究表明，即使是重复囚徒困境（解释相互合作的关键模型之一）也存在隐性形式的敲诈勒索。根据该理论，敲诈者会要求并获取任何盈余中的过多份额，这使他们能够超越任何适应性的合作参与者。为了探究此类策略在与人类对抗时的表现，我们设计了一项经济实验，让参与者分别与敲诈者或慷慨的合作参与者配对。尽管敲诈者在与每个人类对手的对抗中都取得了成功，但敲诈行为带来的收益低于慷慨行为。人类受试者表现出对公平的强烈关注：他们通过拒绝充分合作来惩罚敲诈行为，从而减少自己的收益，更重要的是，减少敲诈者的收益。因此，在社会关系中敲诈他人的前景似乎有限；从长远来看，慷慨更有利可图。
