FIRMS must list foreign workers, blares the headline of London’s Times newspaper today after a speech from the Conservative government’s new home secretary, Amber Rudd. The idea, it seems, is not to list each and every individual but for companies to list the total number of their foreign employees so that they can be “named and shamed”. Conservative Home Secretaries have a tradition of throwing red meat to delegates so it may be that this policy never goes any further. On the BBC’s Today programme this morning, Ms Rudd was emphasising that the policy was only “for consultation”, and if she consults business, she’ll probably get a pretty rude answer. Which business would want to be named and shamed at the top of the list, with all the potential for adverse publicity, demonstrations etc? It’s all a bit reminiscent of the first world war, when shops with German-sounding names had their windows broken and the Royal family changed its name from Saxe-Coburg-Gotha to Windsor. But this was not the only bad idea to come out of the current Conservative conference. First, there was the idea of training more British doctors so that foreign doctors could “go home” after 2025, a policy hardly designed to engender confidence in the many immigrants (like my GP and dentist) who keep the health service going. Then there was the idea of limiting the number of foreign students who can come to British universities (another brainwave from Ms Rudd). As this blog has pointed out before, the Leave campaign had a deep contradiction at its heart. In part, it was driven by Nigel Farage’s UKIP party and its nativist dislike of all immigration (he used the Syrian refugee crisis as a rallying cry, although Britain has barely taken any Syrian refugees). And in part, it was driven by the free-market tendency on Britain’s right, led by the likes of Daniel Hannan and Michael Gove, which disliked EU regulation and wanted Britain to become a hub for global investment, a sort of European Singapore.

It is clear from the Conservative Party’s direction that the first tendency is winning, perhaps because the party sees the chance to seize ground from UKIP, whose latest leader has resigned after just 18 days in charge. UKIP had nearly 13% of the vote in the 2015 election. That is significant because most of the claims for the economic benefits of Brexit were based on the assumption that the second camp would win out.

Instead of sweeping away a thicket of EU regulations, Ms Rudd will be adding more. A reduction of student numbers will require a two-tier visa system. Restrictions on foreign employees would require a “work permit” system in which bureaucrats, not employers, would decide which workers companies could hire. Multinational business might well decide that it is not worth the bother of siting themselves in Britain, which (as seems likely) will no longer be a member of the single market.

Indeed, the proposed measures are economically illiterate. By saying that foreign workers “take jobs that British people should do”, Ms Rudd is propounding the “lump of labour” fallacy—the idea that there is only so much work to go round. This fallacy used to be cited by men who argued that women like Ms Rudd should not be allowed to join the workforce, lest they take jobs from the male sex. But as my colleague Ryan Avent points out in his new book:

Over the long run, large immigration flows are a source of economic dynamism: the people who arrive find jobs, but they also spend and invest, create new firms, pay taxes, generate ideas, and contribute to the resilience and flexibility of the economy.

Foreign students are some of the most useful immigrants of all, being highly-educated and likely to start businesses; one study found that 51% of all billion-dollar start-ups in America were founded by immigrant entrepreneurs. So these are the last people Britain should be discouraging.

Let us hope that this list idea gets thrown in the bin, along with the other proposals we have seen this week. If Britain is to make a success of Brexit, it needs all the help from foreign businesses and workers it can get. We British instinctively recoil from the idea of being asked to produce “papers” to prove who we are and the notion of lists of undesirables. If asked to enumerate their foreign workers, businesses should proclaim in unison “Don’t tell him, Pike”.