You can find this 1938 game among a vast number of Nazi books, cuttings, posters and artefacts that reside, along with the eyewitness accounts of Nazi victims and the signed confessions of the Nuremburg defendants, in a town house in Devonshire Street, London. Juden Raus forms part of the collection of the Wiener Library, the institution that began documenting the work of Hitler’s National Socialists in the 1920s.

Inside the Juden Raus box, the library has retained a review from the SS newspaper Schwarze Korps. The children’s game is criticised for making the “grievous error of suggesting that political problems can be solved by the throw of a dice”. It is a devastating insight into the Nazi mind.

Let me tell you why my grandfather, Alfred Wiener, began this collection. It was because he believed in the power of truth. He believed that the facts would win in the end. He was not a pacifist — you need to be ready to meet force with force. But lies must be fought with truth.

I have always shared this belief. Yet this week, as David Irving begins his sentence in an Austrian jail for denying the Holocaust, my belief, our belief, is being tested. Do I really trust in the power of truth that I have proclaimed so often?

For my grandfather, the Holocaust was not a matter of academic interest and its existence was not a debate in a newspaper. The Nazis made him a refugee from his German homeland, they stole his home and confiscated his property, they killed his wife and imprisoned his children in concentration camps.

In the early 1930s he had trailed desperately around members of the German middle class trying to wake them to the danger posed by the Nazis. He failed. “Hitler condemns the agitation (against the Jews) totally,” he was told by the Secretary of State in the Reich Chancery in the summer of 1932. “He is a decent, idealistic person, if somewhat excitable.”

Still Alfred Wiener retained his belief in the power of the truth. And the Nuremberg and Eichmann trials, the growing historical understanding of the Holocaust and the triumph of liberal democracy over totalitarian doctrine in Europe vindicate that belief. His library has played a role in all of those things.

Yet it is hard to hear the words of Irving and his fellow Holocaust deniers without wishing to be armed with something tougher even than the truth. A baseball bat, for instance, or a pair of Austrian handcuffs.

One of Irving’s contentions, one that helped to bring him a three-year prison sentence, was that “74,000 (Jews) died of natural causes in the work camps and the rest were hidden in reception camps after the war and later taken to Palestine, where they live today under new identities”. Let’s examine this for a moment, shall we?

Yesterday my mother told me of the day, as a young girl in Westerbork concentration camp, she said goodbye to her aunt and uncle and to her 14-year-old cousin, Fritz. These much-loved family members had been listed for the Tuesday transport train to Auschwitz. My mother still has the pitiful letter from her aunt promising that “we will meet again”. But, of course, they never did. David Irving presumably thinks that Fritz and his parents survived and are living in Israel. In which case, the joke is over: they can come back now, don’t you think?

With her own eyes, my mother saw Anne Frank arrive in Belsen (she knew the family), yet still Irving and people like him contend that Frank’s story is fake. And I have been to countless meetings, met dozens of people, who saw the Nazi crimes themselves, lost relatives, were scarred for life, only survived (as my mother did) because of unbelievable moments of good fortune.

It is difficult, even for me now, born in safety, free to bring up my sons as Jews, sitting at a desk typing my article in civilised Britain, it is difficult not to feel anger, rage at Irving. It is difficult not to wish him behind bars. And I do feel rage. But I do not wish him behind bars, not for giving his opinion, not for delivering a lecture, however warped and horrible his opinion is. I still believe in the power of truth. And my belief in truth is what separates me from Irving.

The admirable author Deborah Lipstadt had it right when she destroyed Irving in the courts, challenging his methods as a historian, undermining his reputation, demonstrating his falsehoods and his distortions. It is always tempting to fear the liar and believe, as Mark Twain did that “A lie can make it half way around the world before the truth has time to put its boots on”. But I have more faith than that. I believe that by allowing free exchange, by allowing anyone to assert anything, the truth will triumph,provided that its friends are vigilant and relentless.

So, no, David Irving should not be in jail. We can do better than that. I wish I could tell you that the Irving trial is the only way in which my belief in the power of truth is being tested. But it isn’t. Across the Middle East now, Holocaust denial has become commonplace. It was not difficult last week to spot the banners reading “God Bless Hitler”. The President of the Palestinian Authority denied the full truth of the Holocaust in his PhD. I wish I could tell you that never again will anyone be able to kill millions of Jews, but as we speak Iran is well down the nuclear path and threatens to eradicate Israel.

David Irving is the least of our troubles. But through it all we must hold fast to this: that we must always be ready to meet force with force, but lies — lies we fight with truth.

daniel.finkelstein@thetimes.co.uk

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