If a man asks for a lot of rotting fish, should we blame the fishmonger for giving it him? I'm prompted to ask by David Aaronovitch's piece in the Times attacking the Tories' anti-immigration rhetoric.

The objection to David's argument, of course, is that the government is giving the public what it wants. It wants stinking fish.

Of course, in saying this I sound like the sort of elitist May sneered at yesterday. Nevertheless, people like David and I have a real problem that, in truth, dates back centuries: how can we reconcile democracy with good government?

One answer, advanced recently by Jason Brennan, is that we can't. He says:

Most voters are ignorant of both basic political facts and the background social scientific theories needed to evaluate the facts. They process what little information they have in highly biased and irrational ways. They decided largely on whim. And, worse, we're each stuck having to put up with the group's decision. Unless you're one of the lucky few who has the right and means to emigrate, you're forced to accept your democracy's poorly chosen decisions.

He advocates epistocracy, in which "political power is to some degree apportioned according to knowledge."

That's - ahem - brave. Historically, we've used other ways of reconciling democracy and good government. One way has been to preface democracy with "liberal", so that people's rights act like "trumps" to over-ride the tyranny of the majority. Another way was proposed by Edmund Burke - yes, the same Burke that May praised in her speech yesterday. He said MPs should use deliberative judgment rather than act as mere delegates enforcing the popular will:

Your representative owes you, not his industry only, but his judgment; and he betrays, instead of serving you, if he sacrifices it to your opinion... parliament is a deliberative assembly of one nation, with one interest, that of the whole; where, not local purposes, not local prejudices, ought to guide, but the general good, resulting from the general reason of the whole. You choose a member indeed; but when you have chosen him, he is not member of Bristol, but he is a member of parliament. If the local constituent should have an interest, or should form an hasty opinion, evidently opposite to the real good of the rest of the community, the member for that place ought to be as far, as any other, from any endeavour to give it effect.

Proposals for deliberative democracy such as those from Archon Fung and Joel Rogers among others are attempts to revive this ideal.

Herein, though, lies a paradox. On the one hand, the need to explore these various ways of cleansing voters' preferences has become more pressing in recent years not just because of the rise of racism - let's call it what it is - but because we have ever-growing evidence that people have limited rationality, knowledge and attention. I'm not sure if Jason Brennan, Bryan Caplan (pdf), Daniel Kahneman, Dan Ariely and me would agree upon much, but we agree on this.

On the other hand, though, we've also seen a rise in a crude consumer sovereignty view of politics in which the voter is king whose preferences must be respected and whose "legitimate concerns" must be heeded.

It's this latter view which must be challenged. We must ask: can we change voters' minds? How can we reconcile democracy with better government? Partisan attacks on the Tories' brutal and economically illiterate anti-immigration attitudes are right and necessary, but they deflect attention from much deeper questions.