Roller Skating and Economics
"How are 100 people supposed to skate around the arena without guidance or direction? Each skater traces out a pattern, and the patterns must mesh so skaters avoid injury. That's a complex problem. It would require smart leadership. But it won't get solved! The arena will be a scene of collision, injury, and stagnation. Who will pay for that?!"
If you knew nothing of skating, you would expect catastrophe. Before they knew of skating, people knew of dance performance such as ballet, and to achieve a complex coordination requires a choreographer. Everyone knows that.
Intuition leads us to think that complex problems require complex, deliberate solutions. In a roller rink, the social good depends on getting the patterns to mesh. But no one is minding that good. As your friend describes the business idea, not even the owner intends to look after it. How can the social good be achieved if no one is looking after it?
Yet, we have all witnessed roller skating, and we know that somehow it does work out. There are occasional accidents, but mostly people stay whole and have fun, so much so that they pay good money to participate. The spectacle is counter-intuitive. How does it happen?
via Daniel B. Klein, Rinkonomics: A Window on Spontaneous Order | Library of Economics and Liberty.