Natural Rationality | decision-making in the economy of nature


“Note that he relies on you”; how a single sentence enhances altruism in a Dictator game

In a recent study, experimental economist Pablo Branas-Garza showed that a single sentence is enough to promote fairness. He conducted two experiments, one in a classroom, the other being a regular economic experiments, where subjects had to play a Dictator Game. In every experiments, there was a baseline condition (subjects where presented with a description of the game), and a framing condition: at the end of the text, a sentence reads “Note that your opponent relies on you”. Results: adding that sentence increased donations. As fig. 1 shows, the framing boosts altruism and reduces selfishness: low offers are much rarer.

fig. 1, from Branas-Garza, 2007.

What is surprising is not that subjects are sensible to certain moral-social cues, but that such a simple cue (7 words) is sufficient. The more we know about each others, the less selfish we are.