ABSTRACT
In this chapter the analysis will be refined and enriched, shifting from two to three dimensions. In the transition, the dynamic analysis used in the simple two-dimension world will need to go through some revision: with two strategies, the comparison between the expected utilities was enough to give a fairly precise idea of which form of reciprocity (or non-reciprocity) would emerge in the long run within a given population.1 Going from two to three dimensions, it is worthwhile to use both repeated games and the evolutionary dynamics, because they give two different kinds of information in our discourse on reciprocity.
