A Vincent Reynouard is currently in jail for Holocaust denial in France. A few intellectuals have launched a petition to repeal the such called "Gayssot's law" which punishes human crimes denial, and they received the Noam Chomsky's support. He considers this law as "completely illegitimate and inconsistent with the principles of a free society, as they were understood since the Enlightenment." We know that Chomsky had already been compromised in the eyes of some people, for a text supporting freedom of speech which was used in a preface to a book of Faurisson (a famous French Holocaust denier).
Chomsky's accusers, and those who welcome that he falls again into this kind of trap, do not solve the problem either. Their disagreement clearly shows that there are two irreconcilable approaches concerning free speech. We already knew that. As a result of all this, the famous "Western world values" are not common in the West world. About this topic, there are an American approach and a European approach. And we can see that Chomsky, despite his reputation and his anti-imperialist discourse, advocates American ideology.
The American stance has a logical foundation. To be able to judge an opinion, it must be expressed freely. But this conception has a limit. Once expressed, an opinion can be judged and condemned. Otherwise that will mean that all opinions are equal, which is certainly not the basis of the reference to the Enlightenment. Equivalence of an opinion and its contrary is also logically inconsistent. Equivalence concerns expression, not content.
Moreover, the reference to the Enlightenment is a double-edged sword. The famous short text of Kant, What is Enlightenment, rather poorly argued for freedom of conscience while requiring submission to state arbitrary, Prussian state in his case. Kant's argument, free thinking, but obedience, rather shows the limits of freedom of thought in a dictatorship. This reference doesn't solve anything. The laborious Kantian preaching can be regarded as too careful to be honest.
The other side of the Enlightenment was expressed dramatically by Saint-Just, during the French Revolution: "No freedom for the enemies of freedom." We can consider French Terror as a dictatorship. But it's also logical not to grant freedom to the enemies of freedom, as one cannot claim a freedom which he denies to others by principle. It's a teenagerish (or Americanish) formalism to emphasize the contradiction of some (those who restrict freedom) without seeing the contradiction of others (the enemies of freedom who ask for freedom).
In view with American formalism, the European position is more incidental and pragmatic, contrary to the alleged characteristic of these two continents. The European position does not intend to define abstract transcendent principles, but it assumes setting of rules and limits. These bounds are challengeable, but this is part of the perfectible nature of any system.
Thus, it is absolutely acceptable to prohibit the expression of a specific opinion. This doesn't mean prohibiting saying that earth is flat. Nowadays, this is an abstract hypothesis in Europe - but not in America. This rather amounts practically to prohibit teaching that earth is flat. If all opinions are legitimate, it is possible, even necessary, to teach them all. We know that this particular issue arises in the United States. To justify the illegitimacy of some knowledge, it must be a law that defines what an official truth is. Saying the opposite is illogical or hypocritical.
The question is not whether the Holocaust deniers have a right to believe whatever they want about history. Their claim is not either formal freedom (they obviously are fascists and enemies of freedom). They claim indeed that Holocaust denial is historical truth and that it should be taught. When a Holocaust denier is a history teacher or just a parent, he claims the right to teach Holocaust denial (in the name of academic freedom). Therefore, it should exist Holocaust denial history textbooks recognized by law. The question of teaching Holocaust denial then arises in the same manner as, in America, the question arises whether or not teaching creationism. Saying we must teach one or the other, or neither one nor the other, indeed amounts to define a legal curriculum.
Speaking of "thorough and independent historical research" about the issue of Holocaust denial, as Chomsky did in the first Faurisson's case, is a scholar's classical bias (in addition to be academic hogwash). Many theses, about topics far less disgusting, are nonetheless ridicule bullshits too, and yet rewarded by a PhD degree, including when the candidate is completely destroyed by the board of examiners [at least in France, where deliberations only will be granted by "honorable" (meaning poor), "very honorable" (which means from fair to good), or "very honorable with congratulations of the jury" (which means from good to very good, but often simply "currently fashionable" and "conform to whims of the supervisor whom colleagues will not contradict, it is not the done thing")].
This simple differentiation of "honorable" expresses the socialite and polite issue of "peer recognition." The real question concerns the disrepute of academic titles since higher education is no longer a privilege. Formerly, higher degrees simply meant to be a part of the tiny elite . The diplomas were titles (old meaning of "diploma") of Republican nobility. It worked as long as there were few graduates, and especially very few graduates who not already belong to elite. At that time, a small amount of deserving poor students and a few black sheep among teachers could be tolerated. The real difference is that parents are educated today. They can exert control over syllabuses.
Freedom and Truth
So, the question is the democratic control of teaching contents. But it's another matter to control what is available to adults. However, some adults still have the claim to impose their ideology to children "in the name of freedom." This does not necessarily justify imposing an official truth to adults, but this does not mean that any particular ideology becomes a truth. This is especially true for the enemies of freedom who precisely fight against relativism. The question arises of the criterion of truth, and tradition in this regard is still control by discussion and by law, and in reference to academic system. The process is not perfect and the content is debatable, but there is not much any else alternative.
American formalism consists in saying that if we start banning Holocaust denial, we can ban anything. Besides the fact that anything can possibly be banned already, the problem rather is that formalism assumes a universal rule where there is only a piecemeal approach. The really logical question is simply whether there are principles that allow an a priori determination of all cases that will arise in the future. We can recognize incidentally the Chomsky's generative system. It's quite normal for him to champion this position. But even grammaticality is judged through usage. The true test is empirical.
Like when Kant proposed to denounce a resistance fighter to the police in order to never lie, we can instead consider that the grotesque example of demanding freedom for Holocaust deniers empirically shows the limits of formalism (as a reductio ad absurdum). Since the notion of "limit" is also Kantian, one can consider the possibility that Kant is a wise guy who gave us the freedom to think that his formalism also had some limitations. We know that humor is a means of resistance inside dictatorships. I've also had the opportunity to solve a centennial instance of academic wit in "The Renan Case." Provided always one must be able to decode it! The Kantian joke has lasted two centuries Vs a single one for Renan's.