India, June 20 -- A referendum asks a society to do what a person is almost never asked about her own life: name a number and stop. Not a target, revised upward the moment reached, but a ceiling the system agrees in advance never to cross.

On June 14, Switzerland was asked to set one. The proposal, brought by the country's largest party, would have capped the permanent resident population at ten million by 2050, with tightening measures triggered earlier and the EU free movement agreement at risk if the cap held too long. Turnout reached fifty-nine per cent. Nearly fifty-five per cent said no.

It is easy to read this as a story about immigration, and at the level of posters and platforms, that is what it was. Underneath sat a more inter...