"Fake news" has become a subject of real news. But there's nothing new about "fake news." Holocaust deniers have generated fake news for decades. The deniers have funded "research" "institutes," "journals," books, magazines, videos, websites, newsflashes – all designed to provide a patina of academic respectability to demonstrable falsehoods.

This entire enterprise is devoted to proving that the holocaust – the systematic murder of more than six million Jews in gas chambers, mass shootings, mobile killing units and other means of implementing the carefully planned genocide – simply did not occur. It was made up whole cloth out of "The Jews" for financial and political gain.

No reasonable person with a modicum of intelligence can actually believe that Hitler and his Nazis co-conspirators did not plan the mass extermination of Jews at the Wannsse Conference, and that they did not carry it out at death camps, such as Treblinka, Sorbibor, Majdanek and Auschwitz, Birkenau, as well as by SS mobile killing units that gathered Jews in such places as Babi Yar and the Ponary Woods.

Yet, thousands of people, many with academic degrees, and some with professorial positions, persist in denying the undeniable. These professional liars are given legitimacy by some reputable scholars such as Noam Chomsky, who not only champions the right of these fake historians to

perpetrate their malicious lies, but who actually lend their names to the quality of the " research " that produce the lies of denial. In a widely circulated petition signed by numerous scholars, Chomsky and the other signatories actually described the false history of the notorious denier, Robert Faurisson, as "findings" based on "extensive historical research," thus giving them an academic imprimatur.

I, too, support the right of falsifiers of history to submit their lies to the open marketplace of ideas, where all reasonable people will reject them. The First Amendment to the United States Constitution does not distinguish between truth and lies, at least when it comes to historical events. Just as I defended the rights of Nazis to march through Skokie, and the right of KKK racists to burn crosses on the own property, I defend the right of mendacious holocaust deniers to spin their hateful web of lies. But, unlike Chomsky, I would never dream of supporting the false content of these lies or the phony methodology employed by these liars. Chomsky should be praised for defending the right of Holocaust deniers, but he should be condemned for his complicity in lending substantive and methodological credibility to their false history.

The marketplace is one thing, but let me be clear that I do not believe that any university should tolerate, in the name of academic freedom these falsehoods being taught in the classroom. There is not and should not be academic freedom to commit educational malpractice by presenting provable lies as acceptable facts. Universities must and do have standards: no credible university would tolerate a professor teaching that slavery did not exist, or that the Earth is flat. Holocaust denial does not meet any reasonable standard deserving the protection of academic freedom.

This is not to say that outside the classroom, academics should be limited in their research output, or prevented from publishing improbable claims.

But the difficult questions remain: Where should the line be drawn between demonstrably false facts and controversial matters of opinion that may turn out to contain grains of truth? Should professors be allowed to teach that there are genetic differences between blacks and whites that explain disparities in outcomes? (A Nobel winning Stanford professor of Engineering tried to teach such a course on what he called "dysgenics.") Should the president of a university be allowed to speculate in public about possible genetic differences between men and women regarding the capacity to do ground-breaking work in math and science? (Harvard's former President Lawrence Summers lost his job over that.) How should the media deal with obviously false facts put forward by elected public officials?

I have no problem with courses being taught about the phenomenon of Holocaust denial -- it is after all a widespread concern – just as I would have no problem with courses being taught about the phenomenon of false history, false facts and conspiracy theories. But the classroom, with its captive audience of students being graded by professors, is never an appropriate place to espouse the view that the Holocaust did not take place. The classroom is not a free and open marketplace of ideas. The monopolistic professor controls what can and cannot be said in his or her closed shop. Accordingly, the classroom must have more rigorous standards of truth than the book market, or the internet.

The responsible media should behave in a similar fashion to the professor in the classroom. They should report on the phenomenon of Holocaust denial but not themselves publish unsubstantiated claims that the Holocaust did not occur. There is no way to impose such standards on the free-wheeling internet, where Holocaust denial is rampant. It isn't clear whether the apparent recent surge in online Holocaust denial has been caused by an increase in deniers, or whether closet deniers now have public platforms or social media that they previously lacked.

How then does this all relate to the current phenomenon of false political news and facts? How should the media, academics and the general public deal with politically motivated accusations that the "news" or "facts" they publish are false? Should they report on news and facts asserted by politicians that they have fact-checked and found to lack credibility? Who, in a free and open democratic society, is to judge of whether news, facts, history or other forms of expression are false, true – or somewhere in

between? Do we really want governmental (or university) "truth squads" empowered to shut down stalls that are purveying false goods in the marketplace of ideas? And if not, what are the alternatives?

Censorship is, of course, a matter of degree. There is, moreover, a hierarchy of censorship, with the worst being governmental prior restraint, or criminalization of dissent. Following that would be university denial of academic freedom to express unpopular views outside the classroom. (I do not regard it as impermissible censorship for universities to impose reasonable standards of scholarship in the classroom and for hiring and retention decisions.) Then there is refusal by the media to report on events or issues out of fear of losing readership or advertising revenue. Finally there is self-censorship, based on fear of violating community norms.

The government -- particularly the executive and legislative branches --must be kept away from the daunting task of striking the appropriate balance between speech and the dangers it may pose, because dissent against the state must remain the paradigm of protected speech. The courts will inevitably have to play a role in striking that balance, but should invoke a heavy presumption in favor of speech. The university administration should maintain reasonable standards. In the classroom and hiring decisions, but it must not interfere with the right of faculty and students to express unpopular or even "false" ideas outside the classroom. And the media should articulate and enforce reasonable journalistic standards in reporting and fact-checking on information that some claim is false. In the unregulated world of the internet and social media, there will neither be universal standards nor all- encompassing censorship. There are no "publishers' or censors in the cyber world. In the end, the people will decide what to believe, what to doubt and what to disbelieve. And they will not always make wise determinations in a world where lies spread with far greater speed than when Winston Churchill reportedly observed that a lie makes it halfway around the world before the truth can "get its pants on."

There is no perfect solution to this dilemma. There never has been, and I venture to predict there never will be.

Freedom of speech and the open marketplace of ideas are not a guarantee that truth, justice or morality will prevail. The most that can be said is that freedom of expression is less worse than its alternatives such as governmental censorship, official truth squads or shutting down the marketplace of ideas. Like democracy itself, untrammeled freedom to express hateful and dangerous lies may be the "worst" policy – except for all the others that have been tried over time.

So let the purveyors of fake news – from Holocaust denial to current fake information – try to spread their falsehoods. And let truth tellers respond with facts and evidence.

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