| Abstract | In a public goods game, due to the existence of free-riders, the public cooperation faces a collapse. This is called the social dilemma. Researches show that punishing defection is an effective way of resolving this problem. However, punishment is costly, leading to the appearance of second-order free-riders, which, in turn, prevents punishing behavior from evolving. This situation gives rise to the second-order social dilemma. How does costly punishment arise and evolve? This has become a widely discussed issue in evolutionary research. A computer simulation of the public goods game was conducted; we found that if the returns of the public goods are large enough punishers will obtain evolutionary advantage, so that the second-order social dilemma dissipates. Our research shows, the dominance of cooperators against punishers diminishes as the returns increases, when such dominance becomes sufficiently weak, it is very likely to be offset by the randomness in the evolutionary dynamics. It helps us to better understand why the pursuit of fairness and justice has become a common psychological state and behavioral propensity of human being. Therefore, in public cooperation, social justice is the necessary premise and justice principle is prior to efficiency principle. It also shows that the natural selection endowed mankind with the sense of justice. |