If the second accepts, they get what the first proposed. If the second subject refuses the proposal, neither gets anything. If both subjects were rational and self-interested, and knew each other to be so, the first would propose that he get nine dollars and the second one dollar, a proposal which the second would then proceed to accept on the grounds that something is better than nothing. What one actually observes is a different pattern. Subjects placed in the first position typically offer something like seven dollars for themselves and three for the other.
Subjects placed in the second position typically refuse if offered less than three dollars.
These findings can be interpreted in many ways. An alternative interpretation could be that the second is motivated by the emotion of envy that makes him willing to cut off his nose to spite his face. What I have been saying is that these two interpretations are compatible with one another. The envy may transmute itself into righteous indignation based on a norm of fairness. This rational-choice account overlooks the enormous importance in people's lives both of unjustifiable passion and of their need to justify their actions to themselves no less than to others.