Evolution of empathetic moral evaluation

  1. Arunas L Radzvilavicius  Is a corresponding author
  2. Alexander J Stewart
  3. Joshua B Plotkin  Is a corresponding author
  1. University of Pennsylvania, United States
  2. University of Houston, United States

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.

Article and author information

Author details

  1. Arunas L Radzvilavicius

    Department of Biology, University of Pennsylvania, Philadelphia, United States
    For correspondence
    arunas@sas.upenn.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Alexander J Stewart

    Department of Biology, University of Houston, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Joshua B Plotkin

    Department of Biology, University of Pennsylvania, Philadelphia, United States
    For correspondence
    jplotkin@sas.upenn.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2349-6304

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.

Reviewing Editor

  1. Michael Doebeli, University of British Columbia, Canada

Publication history

  1. Received: December 10, 2018
  2. Accepted: March 19, 2019
  3. Accepted Manuscript published: April 9, 2019 (version 1)
  4. Version of Record published: April 29, 2019 (version 2)

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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  1. Arunas L Radzvilavicius
  2. Alexander J Stewart
  3. Joshua B Plotkin
(2019)
Evolution of empathetic moral evaluation
eLife 8:e44269.
https://doi.org/10.7554/eLife.44269
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