How much should MPs be paid? There seems to be a consensus now that MPs ought not to set their own pay. It ought to be set by a committee. Because they will be independent. And objective.

Let’s leave aside whether independence is really such a good idea (pay will be set by a group of people who can’t be voted out) or even possible (in the end a disbursement of state money has to be voted on by someone, somewhere).

As I said, let’s leave that aside and concentrate on the objective bit. Because, unfortunately, it is where the trouble starts, not where it stops.

What objective standard would a committee apply?

The financial journalist Chris Dillow argues that MPs are not, as they believe, badly paid. They are actually pretty well paid. The annual salary of an MP — £64,766 — puts them in the top 3 per cent of earners. He argues that if we take complaints by MPs about their work at all seriously, then we might actually pay them less.

MPs often say that they have become little more than glorified social workers. And a social worker might be paid £30,000 a year.

Now one might argue that such comparisons are irrelevant. Pay should be set by supply and demand. Safe seats are attracting large numbers of applicants, suggesting that there is no need to pay more. The problem is whether the candidates are of sufficient quality.

But what do we mean by sufficient quality? It entirely depends how good we want them to be. If we could agree on this, one might be able to establish a basket of professions — perhaps GPs, secondary school heads, seniorish civil servants — and make MPs’ pay comparable.

The problem is that the salary of these professions is controlled by MPs. There is something called Goodhart’s law — commonly used to explain fixed currencies — that says that when a measure becomes a target, it ceases to be a measure.

So the moment that these professions are linked to MPs’ pay, their pay will cease to be a good professional measure and become bound up with the debate about politicians.

The other problem with the basket-of-professions approach is that it fails to take into account all the incentives that make people become a politician.

Being an MP is an unstable job and has long and unpredictable hours. At the same time, you can earn other income and you are rewarded with status.

Interestingly, the difficulty with including status in the remuneration calculation is that the correct response to a general fall in the status of MPs, of the sort we are now seeing, would be to raise salary in compensation.

And there is another twist. All of this assumes that we want MPs of broadly similar quality. But we don’t.

We need some very good ones, but the rest can be fine rather than spectacular. And maybe the pay for MPs already reflects that.

This week it was announced that Tony Blair had won a $1 million peace prize.

And he has done well financially since he left office, has Blair. So perhaps MPs’ pay is structured like that for football players.

Superstar wages, as I’ve explained before, work like this: all of us are prepared to pay a little bit each to watch the people at the very top and hardly anything to watch anybody else.

So at the bottom people earn little, but a few at the top earn a fortune. By entering the profession you are sacrificing income, but it is like a ticket to the lottery. If you get to the top you do very well.

If this is right then quite low standard wages for politicians would still attract people of quality, provided that those at the top can still earn the big bucks.

And all this before one considers that people might just possibly go into politics for reasons other than money. Good luck trying to be objective, guys.

Jonah Lehrer — the brilliant author of books and articles that map the brain — has been to the cinema. And he is not happy at what he finds. He notes that State of Play is characteristic of many modern films. It elevates confusion to an art form.

Lehrer explains why such creativity may often be an error.

A study of brain patterns while watching Clint Eastwood in The Good, the Bad and the Ugly shows how almost everyone watches films in the same way with their brain patterns ticking together. The audience sinks into the film. But when their prefrontal cortex — associated with logic and analysis — is forced to be too active, when it can’t be turned on, it interferes with the sinking.

If you wondered why you find complicated films annoying, that may be why.

daniel.finkelstein@thetimes.co.uk

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