HOW can a country decide if ethnic minorities are thriving when it refuses to acknowledge they even exist? France has grappled with this conundrum for years. Under its egalitarian ethos, it treats all citizens the same, refusing to group them into ethnic categories. It is forbidden by law to collect statistics referring to “racial or ethnic origin”. Yet even the casual visitor notices how multi-ethnic France is?and how few non-whites have top jobs. Now a new plan seeks to make it possible to measure “diversity”. Yazid Sabeg, the government's diversity commissioner, has set up a group to find the best way to collect information.

The hope is that this will give France “the statistical tools that will enable it to measure diversity, precisely in order to identify where it is behind, and to measure progress.” That was what President Nicolas Sarkozy called for last year. To American or British ears this plan may sound uncontroversial, but in France it is causing uproar, even though Mr Sabeg wants any data to be offered voluntarily, anonymously and on the basis of self-categorisation.