It's insufficiently appreciated that political differences are due not just to different values but to differences in what people think important.

To take an obvious example, leftists are concerned about inequality whilst many free market rightists tend to be relaxed about it.

Conversely, the free market right worries about the deadweight costs of regulation whilst the left is less concerned by those and more troubled by the costs of austerity. As James Tobin said, "it takes a heap (pdf) of Harberger triangles to fill an Okun gap." By the same token, (some) Tories are troubled by high government borrowing whereas lefties - for now at least - are not.

Immigration, I suspect, is another example. Some rightists - and leftists of the Blue Labour tradition - are concerned by the cultural effects of immigration. And although some on the left positively celebrate multiculturalism and a (perhaps partial form of) diversity, many more of us are just relaxed about it: much of my writing on immigration has been motivated less by positive support for it than by a desire not to see immigrants mistakenly scapegoated for the failures of austerity and capitalism*.

Which brings me to Brexit. Until last year, I hadn't given any thought at all to whether the UK should be a member of the EU or to what form leaving might take. I simply took membership for granted. And I suspect that in this, if not in much else, I am a typical lefty.

From this perspective, the allegation that Labour is confused about Brexit is both true and unsurprising. The party has given the subject little thought, and has no recent intellectual tradition of doing so: yes, membership was an issue in the 70s and early 80s, but it was settled for almost 30 years until the Tories raised it.

Equally, though, Labour's conference organizers are right not to want to vote on the matter. To do so would make the party appear divided to no very good purpose. Labour's approach to Brexit should be as far as possible to present itself as an innocent bystander. Its attitude should be: "this is the Tories' shit; they should shovel it." Brexit has for years been a low-salience issue for Labour though not for the Tories.

Which raises a puzzle. It's no surprise that the Tories are making a mess of Universal Credit; the party has traditionally had little interest in welfare except to want to, ahem, sharpen work incentives. What is odder is that it should also be fouling up Brexit given that many in the party have for years thought about little else**. Which goes to show that there's a surprisingly big difference between being obsessed with a subject and being knowledgeable about it.

* In fact, immigration and inequality have something in common. The best defence of them is that both are mostly harmless by-products of freedom - though as an empirical matter, I believe this is more true of immigration.

** There might be a parallel here with the mess the Russian communist party made of economic policy after 1917: having wanted revolution for years, the party didn't know what to do with it. Yes, there's nothing conservative about the Tories.

Another thing: All this raises the possibility that the BBC can be biased. If, for example, it reports (say) government borrowing more than it reports stagnant living standards and inequality, it's reporting will be biased towards Tory issues.