Oxford, Britain — One thing we’ve learned in the years since the financial crisis is that seriously bad ideas — by which I mean bad ideas that appeal to the prejudices of Very Serious People — have remarkable staying power. No matter how much contrary evidence comes in, no matter how often and how badly predictions based on those ideas are proved wrong, the bad ideas just keep coming back. And they retain the power to warp policy.

What makes something qualify as a seriously bad idea? In general, to sound serious it must invoke big causes to explain big events — technical matters, like the troubles caused by sharing a currency without a common budget, don’t make the cut. It must also absolve corporate interests and the wealthy from responsibility for what went wrong, and call for hard choices and sacrifice on the part of the little people.

So the true story of economic disaster, which is that it was caused by an inadequately regulated financial industry run wild and perpetuated by wrongheaded austerity policies, won’t do. Instead, the story must involve things like a skills gap — it’s not lack of jobs; we have the wrong workers for this high-technology globalized era, etc., etc. — even if there’s no evidence at all that such a gap is impeding recovery.

And the ultimate example of a seriously bad idea is the determination, in the teeth of all the evidence, to declare government spending that helps the less fortunate a crucial cause of our economic problems. In the United States, I’m happy to say, this idea seems to be on the ropes, at least for now. Here in Britain, however, it still reigns supreme. In particular, one important factor in the recent Conservative election triumph was the way Britain’s news media told voters, again and again, that excessive government spending under Labour caused the financial crisis.