On Twitter, LeftOutside asked why a basic income is popular on the internet, but lacks support in the real world.

The answer isn't that a BI is unworkable. Econometric evidence suggest it isn't, and it has been tried in a few places, with mixed-to-favourable results. At worst, this is sufficient to merit further investigation.

Nor is this a left-right issue. Rightists (including Hayekians) can support a low BI, leftists a higher one.

Here, then, are some reasons why I suspect a BI is less popular than it should be.

1. A selection effect.A BI is, perhaps paradoxically, a policy of pessimism. It's based in part upon the idea that governments lack the ability to distinguish between people of high and low needs or between strivers and scroungers - except at high cost - and so should adopt the low-information policy of giving everyone the same. However, politicians are self-selected for having faith in the power of government. They therefore believe - more than the rest of us - that governments can do better than a BI.

2. The power of reciprocity.People hate the idea that others are taking advantage of them - more than they hate the financial loss this causes: this is why "rip off" utility companies are so unpopular. A BI, however, violates the norm of reciprocity by offering skivers something for nothing. Personally, I think this is reasonable in a world of massive excess supply of labour. But others don't.

3.Status quo bias. All welfare systems (including zero welfare) have costs; this is because trade-offs are unavoidable. The question is: which costs would we rather incur? And there's a strong urge for folk to prefer the costs they have than unknown ones. So we tolerate a system with high marginal withdrawal rates, heavy administrative costs, and payment delays that inflict real misery rather than one with other costs.

4. A vicious circle. Because a BI is outside the Overton window, politicians and journalists who want to echo public opinion don't advocate it, and nor do men of "judgment." The upshot is that the idea stays outside the Overton window.

For me, all this means that BI is like land value tax or open borders. It's an idea whose merits far exceed its popularity.