Stefano di Poggio asked a tyrant for mercy and reminded him of an old debt, and was executed for it, which this chapter uses to argue self-interest is the only lever that actually moves people.
Stefano di Poggio thought he had just saved his prince's city. He hadn't. He'd just signed his own death warrant, and he had no idea until the night the guards came for his entire family.
Here's how he got there.
Early fourteenth century, the Italian city of Lucca. A young soldier named Castruccio Castracani claws his way up from nobody to Lord of the city — and he doesn't do it alone. The Poggios, one of the most powerful families in Lucca, back him the whole way. They spill blood for it. People actually die so Castruccio can sit in that chair.
Then he sits in it. And somewhere between taking the title and keeping it, he forgets who put him there. His ambition grows faster than his gratitude does. The Poggios notice.
In 1325, Castruccio is out of town fighting Florence, Lucca's biggest rival. The Poggios decide this is their moment. They line up some of the other noble families and go after him for good. Castruccio had left a governor running the city in his absence. The Poggios have the governor killed. His supporters and theirs start fighting in the streets, and it turns into a full riot. People die. A lot of them.
Then Stefano di Poggio steps in. He's the senior man in the family, and he hadn't even been part of the plot. He walks into the middle of the chaos and calms both sides down. He tells his own family he'll carry their grievances to Castruccio himself and settle this like a reasonable man. Stefano is the smart one in that family. He knows some fights aren't won with a sword.
Castruccio hears what's happened back home and rides for Lucca immediately. By the time he arrives, the city is already quiet — Stefano's doing. He's surprised to find peace instead of a battlefield.
Stefano takes that as a good sign. He goes to see Castruccio, walks him through how he put the fire out, and then — this is the part that kills him — he asks for mercy. He tells Castruccio that the Poggios who moved against him were young, hot-headed, hungry for power but inexperienced. Ignore them, he says. And then he reminds Castruccio of something else: the Poggios helped put him where he is. Surely a good prince repays that with forgiveness.
Castruccio listens to all of it. Calm. Not angry, not even surprised. There will be justice, he tells Stefano. Bring your family to the palace tonight, and we'll settle this properly, together.
As Stefano turns to go, Castruccio adds one more thing. Thank you, he says, for trusting me. For giving me the chance to be merciful.
That night the whole Poggio family walks into the palace. Castruccio has them arrested on the spot. Within days, every one of them is dead. Stefano's body is one of the ones they carry out.
Stefano is the textbook case history uses for anyone who thinks money or justice can shield them from raw power. And he wasn't stupid. He knew exactly who Castruccio was — a man who'd clawed his way up through cunning and cruelty, not kindness. There's a story about Castruccio finding out a close friend had turned on him. He killed the man without a second thought, no trial, no debate. "I didn't kill my old friend," he said afterward. "I killed my new enemy." That's the man Stefano walked in to ask a favor of.
Stefano made two mistakes that night. He asked a cruel man to be merciful. And he expected gratitude — he assumed Castruccio would remember what the Poggios had done for him and pay it back in kind. Castruccio did remember. That was the problem. He remembered exactly what he owed them, and he closed the account the only way a man like him closes anything — by making sure it could never be called in again. If Stefano had offered him something instead, money, a future alliance, anything that pointed forward, he might have lived. Instead he handed Castruccio a bill for an old debt, and reminded him, politely, that his power had once been borrowed. Superior men don't enjoy being reminded of that.
That's the whole shape of Law 13. When you need something from someone, don't lean on their pity. Don't lean on their gratitude either. Aim at their self-interest instead. Show them what's in it for them, not what they already owe you. Remind an ally of a favor you did them and you haven't made a request — you've presented a bill, and nobody enjoys being handed a bill they didn't ask for. They'll find some reason to ignore it. Sit around trusting someone's mercy and you'll get the same result, just slower. Show them instead what they stand to gain from helping you, and something changes — it stops feeling like your problem and starts feeling like theirs too. People who feel like they're helping themselves will back you all the way. People who feel like they're paying off your invoice will look for the exit.
None of this is some clever trick Greene invented. It's just how we're built. We're social creatures, and that's not news — we've lived in groups since survival demanded it. But survival isn't hard for most of us anymore. We still stick together anyway, because of mutual benefit, mutual interest. We need other people to get anywhere in life, and they need us the same way. Over generations that mutual interest curdled into something more self-centered — plain self-interest. That's the ground Law 13 stands on.
So there are really only two ways to ask anyone for anything: from your need, or from their gain. Most people default to the first one because it's the honest-feeling version — you need help, so you say so. But "I need this" is a request aimed at the wrong person. The other party doesn't live inside your need. They live inside theirs.
Try this one this week. Say you need a coworker to cover a meeting or swap a shift. The weak version sounds like, "Remember when I covered for you in March?" That's not a request, it's a guilt trip, and people remember being guilt-tripped a lot longer than they remember the favor that started it. The strong version names their side of the trade: "I'll take your Friday in exchange — the one you've been trying to dump for weeks," or just, "This puts you in the room with the person who signs your review." Now they're not doing you a favor. They're doing themselves one. You've made it easy to say yes, and you haven't put a single thing on the table that they'll resent you for later.
This is not manipulation, and it earns that claim honestly if you're not lying about what you're offering. Look at what pity or gratitude actually does to the other person — it doesn't give them a choice. Refusing feels like betrayal. Agreeing feels like a debt being settled rather than a decision being made freely. Appeal to self-interest instead and you've put something fair in front of them: here's what you get, here's what I get, you decide. That's not a trick, that's the only honest way to ask anyone for anything. You've treated them like an adult who can weigh a trade, instead of leaning on their guilt until they fold. Stefano never gave Castruccio a trade. He gave him a guilt trip and called it loyalty.
None of this works on everyone, and you should know the difference before you try it on the wrong person. Some people genuinely like helping without getting anything back. It makes them feel superior to the people they're helping, and that feeling is the whole payoff — it's why a certain kind of person does charity, so they can feel needed and gracious at the same time. And then there's a smaller group who are just plainly selfless, no superiority complex attached, they simply like being useful. Try to appeal to either one's self-interest and you'll confuse them, because that's not what's driving them. Self-interest works as a reason someone already has — you can't hand people a reason, only an opportunity to act on the one they've already got.
That said — most people are not like that, and you already know it if you've lived any length of time. Greed is one of the most dominant emotions we have, and for ambitious people it works like fuel. We call it a sin, a dark emotion, and fine, it is. But if you want to get ahead of ordinary people, you need it, or at least you need to understand it running in everyone around you. It's the one hunger that never actually goes away, and that hunger isn't a wish for a bigger life — it's a need. Look at anyone in history, or anyone right now, who's ever tried to conquer something. A market, a company, a country. Tell me they weren't greedy. Everybody is self-interested. The ones who genuinely aren't will pay for it, one way or another.
And remember the self-interest runs both directions. You have it. So does everyone you're leaning on. Keep asking someone for things that do nothing for them and the relationship won't survive the pattern. Ask enough times with nothing in it for them, and eventually they say no, or they get mysteriously busy. If someone's still helping you after a run like that, don't mistake it for wanting to. And if any of this still sounds too cold, put yourself where they're standing for a second and ask whether you'd keep saying yes.
That's the part that gets more obvious the older you get, and somehow less painful once it does. This world runs on mutual interest because underneath all of it, it runs on self-interest. You came into it alone. You'll leave it alone. Every man is only for himself. Plan your asks accordingly.
The law above is Robert Greene's, from The 48 Laws of Power.