Evolution of empathetic moral evaluation
Abstract
Social norms can promote cooperation by assigning reputations to individuals based on their past actions. A good reputation indicates that an individual is likely to reciprocate. A large body of research has established norms of moral assessment that promote cooperation, assuming reputations are objective. But without a centralized institution to provide objective evaluation, opinions about an individual's reputation may differ across a population. In this setting we study the role of empathy-the capacity to form moral evaluations from another person's perspective. We show that empathy tends to foster cooperation by reducing the rate of unjustified defection. The norms of moral evaluation previously considered most socially beneficial depend on high levels of empathy, whereas different norms maximize social welfare in populations incapable of empathy. Finally, we show that empathy itself can evolve through social contagion. We conclude that a capacity for empathy is a key component for sustaining cooperation in societies.
Data availability
The data for all figures, code to produce the figures from these data, and the simulation code that generated the data are provided as Source data 1.
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Author details
Funding
David and Lucile Packard Foundation
- Joshua B Plotkin
U. S. Army Research Office (W911NF-12-R-0012-04)
- Joshua B Plotkin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Radzvilavicius et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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