Dear Economist,

I am an immigrant who has lived in England long enough to know that I should never leave home without an umbrella. Many of my colleagues lack my foresight, which means that I often find myself bumping into them in the rain.

I always offer to share my umbrella and have noticed a pattern. Foreigners always accept. Indeed, one New Yorker actually links her arm with mine as we walk. But those whose families have lived here for generations prefer getting soaked.

A cost-benefit analysis would seem to suggest my umbrella is the better option. Yet fear of intimacy appears to trump self-interest. Can you explain?

Cosmo, London

Dear Cosmo,

You do not seem to hold British Londoners in high regard. You think we are stupid, in that we repeatedly leave our umbrellas at home despite the climate. You also believe us to be self-interested; you are sure that we crave the umbrella that you, the clever foreigner, has thought to carry. And you dismiss us as emotionally distant, unlike that perky little New Yorker with whom you so enjoy strolling in the rain.

There is an alternative to the view that we are selfish, unapproachable idiots. It is that we disapprove of umbrellas, viewing them as befitting only Bulgarian assassins. What, after all, is an umbrella but a way of redirecting rain on to other people? The rim of spikes, too, went out with Queen Boudicca. London is a busy place; it would simply be unsupportable if the British behaved as you do. Until recently, a strong cultural norm dealt with this problem. Now that your immigrant umbrellas are causing a public nuisance, there is only one rational response: a hefty congestion charge-style tax on umbrellas.

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