Want to talk? First show me your credentials

The belief that academics can speak only in their expert field stifles debate before it begins, argues Roy Harris.

Freedom of speech is often regarded as imposing some responsibilities on those who exercise it. One such responsibility concerns disclosure of the speaker's identity or, more generally, the speaker's location. Roland Barthes once remarked that whenever you speak, you always speak "from somewhere". By that he meant not just a location in space and time but also a social and intellectual location. Where you speak from counts.

This is the basis of the respect the public has for the academy. Unfortunately, it gives rise to intellectual impostures. The physicist who writes a letter to the press with a row of letters after his name and his university departmental address may be regarded as engaging in a form of intellectual imposture if what he says has nothing to do with physics but expresses his opinion of, say, foreign policy. He is, in effect, say, borrowing the prestige of his university to lend weight to his personal view. Everyone except the simple-minded can see that. That it is done all the same is, however, symptomatic of something more complex.

Those who (rightly) deplore such rhetorical tricks often turn a blind eye to the more uncomfortable fact that, on a larger scale, the same imposture is commonly used to extract academic funding from the public purse. In other words, the implicit assumption is that those who have a record in some mainstream line of research approved in their discipline deserve financial support for that very reason. But this assumption does not stand up to serious scrutiny. It implies that society must trust its academics to know what they are talking about.

The history of ideas, alas, is replete with examples of prestigious experts who got it wrong. These mistakes are duly logged in the record of intellectual progress and are naively regarded by the public as the price to be paid for pushing back the frontiers of knowledge rather than a caution against paying too much attention to academics. Western society turns increasingly to the experts because it no longer trusts religious leaders or politicians to tell everyone what to think. Virtually the whole structure of modern academe is based on the self-serving assumption that experts know best.

As might be expected, academic philosophers have not been backward in coming up with philosophical defences of this position, perhaps the best known being the Popperian doctrine of "fallibilism". Even the physicists Alan Sokal and Jean Bricmont, in their eagerness to expose the intellectual posturing of postmodernists, fall into this trap. They make the disingenuous claim that "the intellectual value of an intervention is determined by its content, not by the identity of the speaker, much less his or her diplomas". The only appropriate response is the remark attributed to the Duke of Wellington: "If you can believe that, Sir, you can believe anything."

Let us be clear about what is in contention here. No one in the academic world supposes that by counting the diplomas of advocates of either side, you can judge which of two conflicting opinions is to be preferred. But that is already a gross oversimplification of the issue. The root of the problem lies in the fact that diplomas, degrees and certificates of academic proficiency are the invention of the academic community itself.

These are the "goods" that the academy sells to the rest of society, and the academy would collapse if society decided that such goods were surplus to requirements. Then, perish the thought, "being an academic" would no longer be a place to speak from.

The engagement of academics in a knowledge-marketing operation means inevitably that they are subject to all the pressures typical of markets.

We see this in the dumbing down of academic "standards" - widely condemned but accelerating at an apparently unstoppable pace, as A-level results clearly show.

We see a more subtle version of it in the duplicitous conception of "academic freedom" that prevails in some quarters. This is restricted to making pronouncements in a field where you are an accredited "expert". In return for this privilege, in all other areas you are expected to bow respectfully to the views of the experts in those fields. This quid pro quo is itself an intellectual imposture at one remove. But unless, as an academic, you accept it, you are deemed to be "speaking from nowhere". The real threat to academic freedom of speech today is an increasing reluctance to speak up from nowhere in case you might appear to be challenging the experts, or even claiming expertise where you have none.J Roy Harris is emeritus professor of general linguistics, Oxford University.