This is what happens a minor irritation turns into a blog post.
I don't think there's much to talk about in this ridiculous debate about whether to 'ban extremists' from the television. The term 'extremists' is deliberately indeterminate; it can mean anything. You construct a norm around anything, and a sufficient deviation from that norm can be considered 'extremist'. Such a policy would be justified by the idea of depriving 'terrorists' of the oxygen of publicity as Mrs Thatcher once put it (or the helium of publicity, as The Day Today almost put it). But the principle could then be extended, with suitable modifications, to practically anyone. So anyone who is for democracy has to oppose it.
The only thing that struck me about the debate was the recurrence of this phrase, "the marketplace of ideas". This actually came chiefly from the government's 'independent reviewer' of 'terrorism' legislation, David Anderson QC, who has been widely quoted as an opponent of bans. What he said was: "I'm a great believer in the market-place of ideas, the good ideas drive out the bad." This struck me as a symptom, a surface appearance of a deeper discursive structure. Although the conceit was raised in this context to oppose counterproductive repression, I should say that I think the immediate ideological function of "the marketplace of ideas" is not to defend 'free speech', but to suggest that speech should be regulated in and through 'the market', which is quite a different matter. It is not that bad ideas shouldn't be suppressed; it is that the state is the wrong mechanism for doing so.
Nonetheless, most people would take the appeal to "the marketplace of ideas" as a sort of obvious, common-sensical, and if anything slightly pious defence of 'free speech'. That fact alone signifies that ideology is working very efficiently. The metaphor - although as I'll suggest, it is a lot more literal than it might appear to be - is worth unpacking. On the face of it, it implies a naive belief that the struggle of ideas is like the struggle between firms, with the stronger destroying the weaker over time. Whereas the struggle between firms supposedly imposes efficient production methods and the correct allocation of resources, the struggle between ideas imposes rigor, stringency, and accuracy. In response to this, it might seem adequate to point out that neither process actually works that way. Firms thrive with all sorts of inefficiencies, and drive out all sorts of efficient innovation; stupid, erroneous and sloppy ideas prosper.
In fact, however, there are two ideas run together here; first the claim that ideological contest is a market - not 'like' a market, but actually a market; second, the claim that 'the marketplace' is a sort of pseudo-Darwinian mechanism for winnowing out weak and unfit ideas.
There is a hackneyed history of the "marketplace of ideas" conceit which traces its lineage to John Stuart Mill, or perhaps even Milton, as part of an evolving tradition of free speech liberalism. Mill did not use the term, and Millian liberalism has nothing to do with its current use. The deliberative discourse advocated by Mill did not, for example, involve the good ideas 'driving out the bad' in a competitive struggle, and I suspect Mill would have been wary of the majoritarian implications of such an idea.
The first, closest approximation of the phrase comes from Supreme Court Justice Oliver Wendell Holmes, who argued against the indictment of two communists in 1919 for distributing literature advocating the cessation of weapons production intended for war against Soviet Russia. Holmes, in his dissenting opinion, argued on the authority of the US Constitution that "the best test of truth is the power of the thought to get itself accepted in the competition of the market". The choice of metaphor underlined the author's fidelity to pro-capitalist, Americanist ideology.
The first use of the actual phrase is in a Supreme Court decision, which found in favour of a publisher's right to lobby politicians, arguing that "like the publishers of newspapers, magazines, or books, this publisher bids for the minds of men in the market place of ideas". In this use, the phrase is more literal than metaphorical - the "market place of ideas" referred to is literally an industry, a market; the ideas are packaged and sold. It subsequently became linked in legal discourses to the defence of democracy: the 'legitimizing myth' that a thriving "marketplace of ideas" allowed members of the public to hold governments accountable.
But this "marketplace of ideas" conceit has a slightly different provenance. The conjugation of an ontology of 'the market' with what Philip Mirowski has characterised as 'thin evolution', is a product of neoliberalism. This specious market ontology begins with a construct, 'the market', which is quite unlike really existing markets. The market is an emergent order, a superior information processor, through which the fragments of knowledge dispersed among various agents are successfully aggregated. While agents are ignorant of the process - indeed, must embrace their ignorance and act exclusively on the basis of their self-interest, their rationally ordered preferences - the market 'knows' better than they what is good and what is bad. This logic is then extended into every sphere of life, erasing the distinction between markets and non-markets.
This market order is then linked to the evolutionary order by means of a trope according to which the market is a pitiless 'selection' mechanism. It is a 'natural' order which 'selects' the correct information in a way that no 'artificial' order could achieve, but with necessarily brutal consequences for the losers. A typical thought experiment to illustrate this would be: suppose several commuters wish to drive across the United States. There are several roads they can travel, but only one has a petrol station (yes, it's called petrol because it is a liquid). Each commuter drives on the roads they prefer, on the basis of the partial information and preferences which they have. But the only ones who actually make it across the country are those who choose the 'correct' road. Those who, for whatever reason, act 'as if' they have the correct information, thrive. The others are taken out of the thought community. Too bad for them, but how else is progress supposed to take place?
This has little to do with the developing science of evolution. Even if the actions of 'the market' truly resembled 'natural selection', which they do not, there is a lot more to evolution than selection. (Although, as Mirowski also points out, citing Dawkins among others, one measure of the success of neoliberalism is the significant in-roads its version of 'thin evolution', laden with economic concepts, has made into evolutionary theory since the Seventies.) But it forms part of a complex and extensive ideological 'common sense', a 'theory of everything' in which brutal competitive struggle operates inexorably at every level of existence: it's just 'how things are'. That weltanschauung is the deeper discursive structure that seems to be adverted to here.