And that is exactly where Greene's argument takes its sharpest turn. If friends carry hidden risks because the relationship assumes equality, then the person who was never your friend — the rival, the opponent, the one who once stood against you — carries a completely different set of assumptions. And Greene argues those assumptions can make them, in certain contexts, more useful. Think of a former opponent who has just been brought into your circle. They know the terms of their position are conditional. They know that every mistake will be watched more closely than a friend's mistake would be. They have no reservoir of goodwill to draw on, no history of shared meals or old loyalty to cushion a failure. That awareness, Greene contends, sharpens them. It makes them more vigilant, more motivated to perform, and more careful not to give you a reason to regret the decision. The digest offers two examples that illustrate this logic. The first is a Chinese emperor who was asked to choose between two candidates for an important appointment. One was a longtime loyal friend. The other had once been his enemy. The emperor chose the former enemy. His reasoning, as Greene presents it, was precise: the friend would assume the relationship was enough. The former enemy would work tirelessly to prove that it was not a mistake to trust him. The incentive structures were simply different. The second example is King Louis XI of France, who Greene presents as someone who consistently preferred to employ men who had once opposed him. Louis understood that their conversion represented something more durable than passive loyalty. A man who had crossed from the opposing side had made a deliberate choice, and that choice carried weight. He had something to demonstrate. A lifelong supporter, by contrast, might feel that his loyalty was already banked — that the relationship owed him something rather than the other way around. That means, in Greene's framework, reliability is not primarily a product of affection. It is a product of aligned self-interest. The friend operates under the assumption that the relationship is sufficient collateral. The former enemy knows it is not. And that knowledge, Greene argues, produces a different quality of attention. It is worth being careful here. Greene is not saying that enemies are always more loyal, or that converting a rival is a guaranteed strategy. His argument is more conditional than that. He is saying that the incentive structure around a former enemy is often sharper, and that sharpness can translate into a more vigilant and self-aware kind of collaboration — provided the conversion is genuine and the terms are clear. Greene's practical advice, as the digest frames it, is not to abandon friendship entirely. He suggests keeping friends for emotional support and private life. But when it comes to the exercise of power — when competence, reliability, and clear judgment matter most — he advises applying standards that friendship tends to blur. And that is the clean contrast the episode has now built across two laws. Law 1 says manage the status of the person above you. Law 2 says manage the incentives of the people around you. Both laws rest on the same foundation: psychological realism rather than moral idealism. Greene is not describing how people should behave. He is describing, in his view, how they actually do. With status and alliances now in place, the episode moves to a third arena where perception becomes power — not who is above you or beside you, but what any of them are allowed to know about what you are actually trying to do.