Content: Provides a systemic explanation based on a series of trials/experiments using competition between computer programs playing the game of prisoners dilemma. The rules used by the programs were up to the designers - this simplest code and the one which won overall was called Tit-for-Tat. It would always cooperate, but would always retaliate once to being cheated before reverting back to cooperation. Axelrod concluded that this behaviour showed how cooperation can evolve and emerge from a competitive system through a reciprocal process. This is still a widely cited work and there is a lively debate about its validity and relevance, which I have addressed in my observations.
Relevance: Influential on my thinking because (1) it shows how cooperation can evolve without the need for extortions to morality in an otherwise competitive situation (2) having taken it to heart I consciously used it as a technique in project management, it worked for me.