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Altruism – A Philosophical Analysis

  1. Christine Clavien,
  2. Michel Chapuisat

Published Online: 15 MAR 2012

DOI: 10.1002/9780470015902.a0003442.pub2



How to Cite

Clavien, C. and Chapuisat, M. 2012. Altruism – A Philosophical Analysis. eLS. .

Author Information

  1. University of Lausanne, Department of Ecology and Evolution, Lausanne, Switzerland

Publication History

  1. Published Online: 15 MAR 2012


Altruism is a malleable notion that is understood differently in various disciplines. The common denominator of most definitions of altruism is the idea of unidirectional helping behaviour. However, a closer examination reveals that the term altruism sometimes refers to the outcomes of a helping behaviour for the agent and its neighbours – that is, reproductive altruism – and sometimes to what motivates the agent to help others – that is, psychological altruism. Since these perspectives on altruism are crucially different, it is important to use a clear terminology to avoid confusion. In particular, we show that the notion of altruism used by biologists profoundly differs from the ones used by philosophers, psychologists and economists in cross-disciplinary debates about human altruism.

Key Concepts:

  • Reproductive altruism refers to a behaviour that increases other organisms' fitness and permanently decreases the actor's own fitness.

  • It is important to distinguish reproductive altruism from cooperation, in which both partners gain direct fitness benefits.

  • Reproductive altruism decreases the direct fitness of the altruist and thus its persistence in the course of evolution requests an ultimate explanation.

  • Kin selection, the indirect transmission of genes through relatives, is the key process explaining the evolution and maintenance of reproductive altruism.

  • Psychological altruism refers to an other-directed motivation to help and increase others' welfare independently of self-directed calculations.

  • Psychological altruism is a proximate mechanism; in contrast to reproductive altruism, it may confer direct fitness benefits.

  • To avoid misunderstandings, it is important to identify which form of altruism is at stake in interdisciplinary literature about human altruism.


  • altruism;
  • helping;
  • kin selection;
  • Hamilton's rule;
  • human altruism;
  • motivation;
  • proximate versus ultimate explanation;
  • psychological altruism;
  • reproductive altruism;
  • weak altruism