Lying, Integrity, and Cooperation

While talk is cheap to some, it is expensive to others for whom moral considerations come into play. We employ a simple two-stage modified prisoner's dilemma game where integrity is endowed on a continuum to analyze when agents will lie in random economic interactions. If there is sufficient integrity in the population, all agents make a promise in the first stage to cooperate in the second. Some agents always lie, some always tell the truth, and some behave conditionally. Enhanced cooperation is a byproduct of integrity. In a second random interaction without the possibility of exit, some agents “switch” their behavior, that is, some who lied in the first period now tell the truth in the second (they've “reformed”), and some who told the truth in the first period now lie in the second (they've become “cynical”).