Public Choice, the economist James M. Buchanan explained, is built on the “homely” proposition that politicians are just like the rest of us. We call this “behavioral symmetry.” They have their own interests, and they try to satisfy those interests. Furthermore, we can understand people’s behavior in the voting booth and the bureau using the same tools we use to understand their behavior in the supermarket and the boardroom.

When I lived in Memphis, I would regularly see signs for a local congressional representative proudly announcing that he was “fighting for Memphis.” Fighting who, I wondered, and for what? The answers were pretty obvious. He was fighting the rest of the country for as much as he could get from the public till. To the best of my knowledge, politicians do not generally say “no, we don’t need to spend this money in my district” or “we already have too much; let’s use these resources somewhere else.”

But most importantly, assuming people are “self-interested” does not mean they are evil, selfish, or venal. It just means they have interests other people may not share, and they do things to make them better off however they choose to define that. Public choice applies even when people are perfectly selfless as long as they disagree about what will do the most good for the world.

One wholly selfless humanitarian might think education is sorely underfunded. Another wholly selfless humanitarian might think health care is sorely underfunded. How will they vote? How will politicians who seek to curry favor with them act? Economics does not build on assumptions about the worst kind of selfishness, nor does it endorse them. It builds, rather, on the simple fact that people disagree about what is the good, the true, and the beautiful.

Indeed, standard economic models saying people “maximize consumption” work just as well if we define “consumption” in wholly other-interested ways. The “consumption” comes from the fact that resources are consumed in the process of satisfying our wants. The economic problem doesn’t change fundamentally if we assume people want to maximize everyone else’s consumption of food, clothing, and shelter rather than their own. Economics predicts, however, that people will be less careful with others’ money than their own, and experimental evidence from my Samford colleague Joy A. Buchanan and Weber State’s Gavin Roberts suggests they are.

No two people can eat the same kernel of grain, so even if you are wholly selfless there will, at any point in time, only be so much that can go around. And people who have different ideas about what is best for the poor—eat the grain now versus plant the grain and have more later—will run into the same conflicts plaguing even the most selfish among us.

Economics does not tell you anything about what your preferences should be. It develops insights based on the conviction that people have different ideas about what is good and the fact that resources are scarce. Economics per se doesn’t offer a theory of the good, the true, and the beautiful because it can’t. For that, we look to the humanities and natural sciences. Good places to enter into the Great Conversation with gratis texts include Project Gutenberg, the Online Library of Liberty, and (for audiobooks) LibriVox. Economics is an analytical framework, not a set of propositions about what is good and right. It’s a much more powerful analytical framework than we might think at first, as well: even Mother Teresa and Albert Schweitzer faced scarcity and had to allocate the resources at their disposal among competing ends.

When public choice economists invoke “behavioral symmetry,” they aren’t saying that we should assume people are evil. Rather, we should simply assume that people have different ideas about the contents of the good, the true, and the beautiful, and just as we try to maximize these in the market, we try to maximize them in the political sphere, as well.