Many of you believe that our politics is broken. I suspect this is right, in a particular sense.

What I mean is that pretty much all social institutions can be thought of as selection devices. The problem with politics is that these devices are working less well than they used to. Here are five examples of what I mean.

1. Parliamentary candidates used to be selected by mass-membership parties in which an ability to persuade or to build wide support was valued. Today, parties have been captured by fanatics and narcissists who select candidates in their own image; this problem has been exacerbated by the fact that there are bigger rewards on offer outside of parliament, which (at the margin) selects against some able people.

2. Ministers used to be selected as the most able MPs. Today, more premium is placed upon toeing the party line. The wretched Chris Grayling or Liam Fox thus occupy office because they are Brexiters, rather than because of any competence or character.

3. MPs used to see their role in Burkean terms - as being members of a "deliberative assembly" exercising independent judgment. In this way, the "hasty opinion" of the public was sometimes selected against. Today, with the rise of referendums and conception of politics as just another arena where the customer is king, this conception has declined.

4. We used to think that free debate would select for good ideas and against bad. As Mill wrote:

[Mankind's] errors are corrigible. He is capable of rectifying his mistakes by discussion and experience. Not by experience alone. There must be discussion, to show how experience is to be interpreted. Wrong opinions and practices gradually yield to fact and argument.

Today, this seems doubtful. People are asymmetric Bayesians. Confronted with opposing evidence, thy double-down (pdf) on their prejudices rather than yield to fact. Debate doesn't therefore select properly for better ideas. (The BBC's impartiality between truth and falsehood reinforces this failure).

5. Maybe there was a time when the media selected for intelligence or at least against egregious scumbags. Today, it doesn't. In the 90s, David Irving was shut out of the public domain. Today, though, he'd have lots of Twitter followers and broadcasters, desperate to attract the viewers and attention that comes from controversy, would no doubt invite him onto their shows - as they do with Bannon, Gorka and Farage. This lust for mindless controversy - what I've called politics as wrestling - means that buffoonish charlatans like Johnson get attention whilst decent thoughtful MPs such as Jesse Norman do not. (A lot of the left should also be blamed here for preferring the moralistic posturing of "calling out" to engaging with serious ideas.)

Now, I'm not pretending that there was ever a golden age of perfect deliberation. There never was. Politics has always had a share of duffers and crooks. I just suspect that its selection mechanisms are more dysfunctional now than in the past. Bad ideas and bad people are more likely to be selected for rather than against.

Our question, therefore, must be: how can we build better selection mechanisms? Paul Evans deserves huge credit for asking just this.

For me, at least part of the answer would be institutions (pdf) of deliberative democracy - mechanisms such as citizens juries which consider evidence and which help equalize political power by giving a say to the poor and downgrading the influence of the mass media. Paul Cotterill is right to call for a more Habermasian politics.

Merely saying this, of course, draws attention to the big problem here. Our current broken selection mechanisms serve the rich and powerful very well: why should they take a risk with deliberative, inclusive evidence-based policy-making? Perhaps, therefore, there is a tension between actually-existing capitalism on the one hand and a well-functioning democracy on the other.