Destinations and paths

In Living Together: Inventing Moral Science (2023), Chapter 3 is titled “Justice as Traffic Management.” Schmidtz treats traffic lights and related rules as a working model of justice and of the social infrastructure that makes living together possible.

He applies the same picture to property, convention, and other institutions: they function as traffic management. They get in the way just enough to keep people out of one another’s way, so individuals can pursue their own projects and a better life together.

Part of the traffic management might be universally agreed upon so that at a particular intersection the autonomous actor must stop, not even turn right on red. Some other directionals may allow for private discretion within the greater framework. If the left hand turn arrow is flashing yellow. The driver can make a judgement call about the distance between the on-coming cars and decide when to go forward with their plan.

Think of people as drivers. Each has a destination of their own. Some want the coast, some a quiet town, some a high ridge. Justice, on Schmidtz’ account, is not the destination. It is the traffic system that lets them move without wrecking one another: lanes, lights, turn-taking, settled expectations. A good system does not rank destinations. It does not need to know where you are going. It only needs everyone to know whose turn it is at the intersection.

Now add some landscape. There are knolls and dips and mountain ridges and valleys.

Utopians treat justice itself as a summit. They imagine one peak so high that, once you are on it, nothing more can be asked. From there they look down at ordinary roads and call them incomplete. The climb is treated as a detail: if the peak is perfect, difficulty is a practical inconvenience, not a reason to doubt the map. The temptation is to treat other people’s destinations as detours from the peak, and to use the traffic system as a convoy that must all go the same way.

Realists refuse that picture. They say the shared landscape is not a single mountain we are all climbing. What we can actually see are pits: slavery, famine, persecution, gridlock, institutions that stop people from moving at all. Those are real. The perfect peak is a drawing. A society that works does not drag everyone toward one imaginary summit. It keeps the roads open so that each person can climb a mountain of their own choosing—or stay in the valley if that is their life.