Why does the US Senate work the way it does? Why do some leaders build roads while others steal the money? Why do regulations so often end up serving the industries they're supposed to police — you need a set of lenses that apply everywhere. That's what Mechanism Foundations is: the underlying forces that shape organized power, before you zoom into any one country. The most disorienting of those lenses is public-choice theory. It came out of economics in the 1950s and 60s, and its core claim is simple enough to say in one sentence: politicians, bureaucrats, and voters are just people, and people respond to incentives. That's it. But the implications are genuinely strange.

The standard story of government is that it's a planning operation. Citizens identify a problem. Leaders design a solution. Bureaucrats implement it. The goal is the public good. James Buchanan (1919–2013, United States) — the economist who won the Nobel Prize in 1986 for developing public-choice theory — looked at this story and said: you're applying two completely different models of human behavior depending on whether someone is in a market or in government. In a market, you assume people pursue their own interests. In government, you suddenly assume they pursue everyone else's interests. Why would the same person switch modes the moment they take a government salary? Buchanan's answer: they don't. And once you stop assuming they do, government starts to make a lot more sense.

This is the core of public-choice theory: the incentives facing political actors are structurally different from the incentives facing a city planner trying to optimize a bus route. A politician's product is votes. To get votes, you deliver visible benefits to organized groups who will notice, remember, and show up on election day. You avoid imposing visible costs on those same groups, even when the costs are economically justified. The result looks a lot like a market — just one where the currency is votes and the product is policy. Corn subsidies exist not because they're good agricultural policy (most economists think they're terrible) but because corn farmers are a concentrated, organized constituency who care intensely about this one issue. Consumers who pay a few extra cents per box of cereal have no idea and no incentive to organize against it. The farmer shows up. The consumer doesn't. The subsidy persists. This is what Buchanan called the logic of concentrated benefits and diffuse costs. It's why programs that most people would vote to eliminate in a referendum somehow never get eliminated by the people we elect to eliminate them.