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The alliance hypothesis for human friendship.
Peter DeScioli1, Robert Kurzban
1University of Pennsylvania, Philadelphia, PA, USA. descioli@psych.upenn.edu
Plos One
|June 4, 2009
Summary
Human friendship may be driven by cognitive mechanisms for building support groups. People rank friends based on their perceived position in others
Area of Science:
- Evolutionary Psychology
- Social Cognition
- Game Theory
Background:
- Human friendship is explored through its evolved functions, proposing cognitive mechanisms for assembling support groups against conflicts.
- Game theory identifies computations about friends that enhance performance in multi-agent conflicts.
- Hypotheses suggest egocentric and allocentric social representations, motivation for information concealment, and friend-ranking based on partners' rankings.
Purpose of the Study:
- To investigate the alliance hypothesis as an explanation for human friendship.
- To test predictions derived from game theory regarding friend-ranking computations.
Main Methods:
- Three empirical studies were conducted to test the alliance hypothesis.
- Analysis focused on participants' rankings of their closest friends.
Main Results:
- A key finding, replicated across studies, showed that individuals' friend rankings correlate with their perceived rank among their partners' friends.
- This relationship persisted even when controlling for factors like perceived similarity, familiarity, and benefits.
Conclusions:
- The results support the alliance hypothesis as a potential explanation for the cognitive underpinnings of human friendship.
- Further research into this hypothesis is warranted to advance understanding of friendship's evolved functions.
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