Externalizing between conformers

or Why I could conceivably support banning smoking, part 1

Suppose that people are rational and their goals are consistent, and they are free to choose whatever activities they like, as long as they don’t harm others. Suppose we don’t care about equality or whether lifestyles are nihisistic, or anything else Wikipedia claims might be wrong with libertarianism. Should we expect people to approximately end up with the best sets of behaviour? If they smoke, should we infer that they like smoking more than they dislike having lung cancer far in the future? If they watch intellectual documentaries rather than porn should we assume that they have wisely established that they like looking smart more than raunchy fantasy? Many think so, and support libertarianism for this reason.

This makes sense if humans are independently choosing activities. But the all time favorite activity of nearly everyone is doing what other people are doing. This makes such an argument more complicated.

Imagine everyone is doing A. Everyone likes doing B more than doing A, but not as much as they like conformity. There would be a huge gain to a coordinated shift to B, but nobody moves there alone. In some such situations those involved arrange coordination, but often it is impossible. If there are many equilibria like this, and no means to move to better ones, intervention by someone with the power to force a coordinated move could be a great thing.

A good example of this I saw was during first year at college. Everyone used to go to Southpac to drink. I was baffled, as it was probably not just the worst night club around, but actually the least pleasant place I had ever been, possibly but not definitely excluding ankle deep in poo and mud with rotten meat juice running up my arms and dogs clawing at me. When I asked, everyone said they hated it, but it was overall the best place to go, because that’s where everyone else went. It seemed that there were too many people for any student to easily coordinate everyone going somewhere else, so the original equilibrium remained until Southpac was closed down for using (cheap, poisonous) methylated spirits in the drinks. The student council got sponsorship somewhere else, and everyone else went there instead.

Roger
Southpac Elsewhere
Everyone else Southpac 2 1
Elsewhere 0 3

Payoffs for Roger in choosing a nightclub

In the above table, assume ‘everyone else’ is made up of people in the same situation as Roger. Roger doesn’t want to dance alone, so he gets 2 happiness from going to the same club as everyone else. He also doesn’t like being attached to the floor by stickiness and vomit, but it’s less of an issue, so he gets 1 happiness from going anywhere but Southpac. Everyone going to Southpac and everyone going elsewhere are both Nash equilibria, but the going elsewhere equilibria is half as good again.

Why wouldn’t people be able to coordinate to change? One reason is group size or ungainliness. The other is that liking the current activity sends a signal. Suggesting everyone choose a different activity to signal group loyalty for instance marks you as disloyal as fast as refusing to participate alone does.

This doesn’t necessarily mean government intervention is necessary. That might still be worse than freedom, because if the government were to legislate culture it would be hard to verify that they were doing it in only the justified instances. It does seem to mean that free choice will not lead to the best outcomes however, undermining some justification for libertarianism.

Whether we should be concerned about externalities that others choose to bear is a matter of contention. If you should be encouraged against an activity because others want to do the same as you and they don’t like that activity, you should probably also be encouraged not to demonstrate homosexuality where it is unpopular or be ugly for instance. These also harm others, because they choose to disapprove. I think most would disagree that externalities caused by others choosing to care what you are doing should be regulated. I suspect such a sentiment is just a heuristic for allowing those who have the greatest interests in something having control over it, so people should usually be allowed to do unpopular things visibly, but in this case forced change may be a good thing.