As I write, controversy rages over Puffin’s rewriting of Roald Dahl, and Bloomsbury’s apparent attempt to squash Nigel Bigger’s book, Colonialism. Of course, this sort of thing can be counterproductive. A common economic consequence is a huge boost in sales; Bigger’s book is the current best seller. Indeed, the “outlaw sell” is a standard marketing strategy. Think of the 1980s band Frankie Goes to Hollywood. They had to remake the Relax video no less than three times before it was outrageous enough to be banned. Or Malcolm McLaren’s virtuosic surfing of the wave of censorship that surrounded The Sex Pistols. However, here I’m more interested in the implications of censorship for the economy as a whole.

Let’s go back to a country show in the summer of 1906. Darwin’s cousin, Francis Galton, a foundational figure in the development of statistics, took great interest in a competition to guess the weight of an ox. He obtained the tickets to see if there was any correlation between a person’s occupation and the accuracy of their estimate.

According to documents I’ve tracked down in a Cambridge college library, Galton discovered that the butchers’ estimates were clustered around the same value; it was close but not correct. The estimates of the farmers were also clustered around a particular weight, this time a few per cent too high.

When “deviant” opinion is closed down, we put the future in jeopardy

It’s impossible to overestimate the importance of this. Most people only consider information their prior training and experience have led them to see as relevant – anything else will be ignored.

Every butcher formed his estimate using exactly the same information used by every other butcher, which was gleaned from the practice of buying, preparing, and selling meat. Similarly, the farmers’ informational filter came from the experience of rearing and selling cattle.

We can see the data considered by the members of these two groups as the “acceptable” set, precisely akin to the data that counts as relevant in the practice of “normal science”.

Experts become experts through the process of training and socialisation. That process sets a cast-iron limit on the kinds of data they consider appropriate in forming judgements.

This brings us to the most interesting part of Galton’s findings. He decided to average the entire set of estimates. Astonishingly, the result was within 1% of the correct value. This is “the wisdom of crowds” and it’s a result that has been replicated again and again.

What’s going on here?

There were, as you might expect, a few wildly inaccurate estimates, some way too high, some way too low – but these simply cancelled out. More important were the estimates nearer to the correct value made by people who were neither farmers nor butchers.

These estimates were based on information that wasn’t taken into account by the others. The professional tracker looked at the depth of the ox’s hoof prints, the coachman compared the size of the ox to horses whose weight he knew, and so on. Crucially, it was the estimates of these outliers that pulled the average towards the correct value.

What does this have to do with the economic consequences of censorship? A common argument in favour of censorship is that claims that are “obviously wrong” must be kept out of public debate. More perniciously, some think the opinions of “morally reprehensible” people should be suppressed… however moral reprehensibility happens to be defined by the totalitarians du jour.

What’s wrong with that? Well, the problem for society in general, and the economy in particular, is that we live in a state of ineliminable ignorance. We have, a priori, no way of knowing whether a divergent opinion is crazy or brilliant, indeed most brilliant ideas seem pretty crazy at first.

Often, developments that benefit society economically, and in every other way, begin with people who don’t subscribe to the consensus; people who seem, at best, obviously wrong; people who would fall foul of a censor.

This means that when “deviant” opinion is closed down, we put the future in jeopardy.

Furthermore, a prerequisite for the maintenance of economic wellbeing is ceaseless innovation. New problems require new solutions, and without freedom of thought and expression innovation collapses. This has been the story of every closed society in history.

Finally, although I’m specifically concerned with the economic implications of censorship here, I think these are the least of our worries. Censorship takes many forms and as Ray Bradbury says: there’s more than one way to burn a book. In the chilling words of Heinrich Heine: “Where they burn books, eventually they will burn people.”

Peter Lawlor is the Principal Economic Advisor to 7Ridge Capital and an adviser to senior Wall St figures. These are strictly his own views