Friday, April 13, 2007

Egalitarian Motives

The theme of human nature has long dominated debates in political theory. Are human beings, as a species, primarily motivated by self-interest or altruism? The answer one gives to that question will have a great influence on what one thinks it is possible for human societies to achieve and the kinds of institutions (e.g. economic, political, etc.) we should implement.

The latest issue of the journal Nature has an interesting piece entitled "Egalitarian Motives in Humans". Here is the abstract.

Egalitarian motives in humans
By Christopher T. Dawes, James H. Fowler, Tim Johnson, Richard McElreath & Oleg Smirnov

Participants in laboratory games are often willing to alter others' incomes at a cost to themselves, and this behaviour has the effect of promoting cooperation. What motivates this action is unclear: punishment and reward aimed at promoting cooperation cannot be distinguished from attempts to produce equality. To understand costly taking and costly giving, we create an experimental game that isolates egalitarian motives. The results show that subjects reduce and augment others' incomes, at a personal cost, even when there is no cooperative behaviour to be reinforced. Furthermore, the size and frequency of income alterations are strongly influenced by inequality. Emotions towards top earners become increasingly negative as inequality increases, and those who express these emotions spend more to reduce above-average earners' incomes and to increase below-average earners' incomes. The results suggest that egalitarian motives affect income-altering behaviours, and may therefore be an important factor underlying the evolution of strong reciprocity and, hence, cooperation in humans.