Something beautiful

[Cal Miles]

The Outbreak of Cooperation among Success-Driven Individuals under Noisy Conditions

According to Thomas Hobbes' Leviathan [1651; 2008 (Touchstone, New York), English Ed], "the life of man [is] solitary, poor, nasty, brutish, and short," and it would need powerful social institutions to establish social order. In reality, however, social cooperation can also arise spontaneously, based on local interactions rather than centralized control. The self-organization of cooperative behavior is particularly puzzling for social dilemmas related to sharing natural resources or creating common goods. Such situations are often described by the prisoner's dilemma. Here, we report the sudden outbreak of predominant cooperation in a noisy world dominated by selfishness and defection, when individuals imitate superior strategies and show success-driven migration. In our model, individuals are unrelated, and do not inherit behavioral traits. They defect or cooperate selfishly when the opportunity arises, and they do not know how often they will interact or have interacted with someone else. Moreover, our individuals have no reputation mechanism to form friendship networks, nor do they have the option of voluntary interaction or costly punishment. Therefore, the outbreak of prevailing cooperation, when directed motion is integrated in a game-theoretical model, is remarkable, particularly when random strategy mutations and random relocations challenge the formation and survival of cooperative clusters. Our results suggest that mobility is significant for the evolution of social order, and essential for its stabilization and maintenance.

Dirk Helbing and Wenjian Yu
Swiss Federal Institute of Technology Zurich - Department of Humanities, Social and Political Sciences (GESS)

National Academy of Sciences USA (PNAS), Vol. 106, No. 8, pp. 3680-3685, 2009


Note: As the abstract explains, the individuals (initially red squares in the video) in this model are selfish, able to defect, imitate successful strategies, don't inherit behavioral traits, and have no reputation mechanism beyond direct observation. When the model is run, clusters of cooperation (blue) spontaneously emerge and eventually spread over the entire grid (yellow is going from cooperation to non-cooperation, green is the reverse).

The important points, imo, are (1) that cooperation naturally emerges and spreads in a social order of self-interested individual agents and (2) that individual mobility - the ability of the individual to leave spatially or effectively - is a key factor in creating and maintaining stable social order (via maintaining cooperation as preferable for self-interested agents).

Attachment: Journal article.