The timing of Austria's conviction and imprisonment of David Irving for denying the Holocaust could not have been worse. Coming after the deaths of at least 30 people in Syria, Lebanon, Afghanistan, Libya, Nigeria and other Islamic countries during protests against cartoons ridiculing Muhammad, the Irving verdict makes a mockery of the claim that in democratic countries freedom of expression is a basic right. We cannot consistently hold that cartoonists have a right to mock religious figures but that it should be a criminal offense to deny the Holocaust. I believe that we should stand behind freedom of speech. And that means that David Irving should be freed. Before you accuse me of failing to understand the sensitivities of victims of the Holocaust, or the nature of Austrian anti-Semitism, I should say that I am the son of Austrian Jews. My parents escaped Austria in time, but my grandparents did not. All four of my grandparents were deported to ghettos in Poland and Czechoslovakia. Two of them were sent to Lodz, in Poland, and then probably murdered with carbon monoxide at the extermination camp at Chelmno. One fell ill and died in the overcrowded and underfed ghetto at Theresienstadt. My maternal grandmother was the only survivor. So I have no sympathy for David Irving's absurd denial of the Holocaust - which he now claims was a mistake. I support efforts to prevent any return to Nazism in Austria or anywhere else. But how is the cause of truth served by prohibiting Holocaust denial? If there are still people crazy enough to deny that the Holocaust occurred, will they be persuaded by imprisoning people who express that view? On the contrary, they will be more likely to think that people are being imprisoned for expressing views that cannot be refuted by evidence and argument alone. In his classic defense of freedom of speech in On Liberty, John Stuart Mill wrote that if a view is not "fully, frequently, and fearlessly discussed," it will become "a dead dogma, not a living truth." The existence of the Holocaust should remain a living truth, and those who are skeptical about the enormity of the Nazi atrocities should be confronted with the evidence for it. IN THE aftermath of World War II, when the Austrian republic was struggling to establish itself as a democracy, it was reasonable, as a temporary emergency measure, for Austrian democrats to suppress Nazi ideas and propaganda. But that danger is long past. Austria is a democracy and a member of the EU. Despite the occasional resurgence of anti-immigrant and even racist views - an occurrence that is, lamentably, not limited to countries with a fascist past - there is no longer a serious threat of any return to Nazism in Austria. By contrast, freedom of speech is essential to democratic regimes, and it must include the freedom to say what everyone else believes to be false, and even what many people find offensive. We must be free to deny the existence of God, and to criticize the teachings of Jesus, Moses, Muhammad and Buddha, as reported in texts that millions of people regard as sacred. Without that freedom, human progress will always run up against a basic roadblock. Article 10 of the European Convention on Human Rights and Fundamental Freedoms states: "Everyone has the right to freedom of expression. This right shall include freedom to hold opinions and to receive and impart information and ideas without interference by public authority and regardless of frontiers." To be consistent with that clear statement - and without the vague qualifications of Article 11, which threaten to render it meaningless - Austria should repeal its law against Holocaust denial. Other European nations with similar laws - for example, Germany, France, Italy, and Poland - should do the same, while maintaining or strengthening their efforts to inform their citizens about the reality of the Holocaust and why the racist ideology that led to it should be rejected. LAWS AGAINST incitement to racial, religious or ethnic hatred, in circumstances where that incitement is intended to - or can reasonably be foreseen to - lead to violence or other criminal acts, are different, and are compatible with maintaining freedom to express any views at all. Only when David Irving has been freed will it be possible for Europeans to turn to the Islamic protesters and say: "We apply the principle of freedom of expression evenhandedly, whether it offends Muslims, Christians, Jews or anyone else." The writer, a professor of bioethics at Princeton University, is the author of, among other books, Pushing Time Away: My Grandfather and the Tragedy of Jewish Vienna. This piece was provided through www.project-syndicate.org.