The argument is very simple: if you live after the Holocaust, the worst thing in the world is to be a Nazi. That is why Israel is the worst thing in the world, because they are Nazis. It's a blasphemy. But sometimes the big lie, if repeated often enough, does win. And we have to realise that some very, very big lies in history have had very distinguished intellectual fellow travellers.

DJ: In the book you ask some very fundamental questions. Is there still such a thing as a Jewish people? What do we now still have in common with them? You quote some distinguished commentators who doubt this, who fear that this ancient covenant has now broken apart and that people are being tempted either by secularism, by assimilation, by the very understandable feeling that after the Holocaust, after so much suffering and persecution, perhaps it's better not to be Jewish at all, perhaps this is too big a burden to pass on to your children. You say this is very much the attitude in America of the post-Holocaust generation, to which, in a sense, we both belong.

JS: I'm speculating there because nobody's said this, but I'm making that inference, yes.

DJ: It's clearly a problem because the statistics and the demography back this up. But then on the other hand there is the opposite danger of retreating back into the ghetto, of the most successful Jewish communities being perhaps the most Orthodox, but who are not engaging with the wider world — or in many cases they aren't. So that makes you a rather rare figure, because in a sense you are engaging with the wider world, but you're not turning your back on the heritage of the nation. In a country where the Court of Appeal takes it upon itself to tell Jews who is a Jew and who isn't a Jew, we have a problem, don't we? You need to know this yourselves if those around you are arrogating to themselves that right. 

JS: Yes. Those are such fundamental questions that I really had to write a book to answer them and the answer comes along three dimensions.

The first was my attempt over a whole series of books — Radical Then, Radical Now, and The Dignity of Difference, To Heal a Fractured World — to create a paradigm shift that is contained in those four words: the dignity of difference. In those words, I tried to reframe Jewish identity by universalising particularity. We are not all the same, and precisely because we are not all the same, we each have a unique contribution to give to the common good. We build together the common good of Britain as a country in To Heal a Fractured World and The Dignity of Difference. It is a human project. So I tried to use that paradigm shift to break through this thing between the particularists, who turn inward to preserve their identity but lose any real influence on society, and the universalists, who save the world but who don't have Jewish grandchildren.

Number two is something I've set out in a chapter called "The Jewish Conversation". We are not all of the same opinion. I had a public conversation with Amos Oz in Israel, and he began with this wonderful remark: "I'm not sure that I agree with Rabbi Sacks on everything, but then on most things I don't agree with myself!" 

He used this to produce the classic and unique Jewish heritage of what we call "argument for the sake of Heaven" — I don't know of any other religious literature, including the religious literatures of the holy texts of Christianity and Islam, where human beings argue with God, where God argues with human beings, where He wrestles with them, and we wrestle with Him. There is, as far as I know, no counterpart to those dialogues of Abraham, Moses, Jeremiah, Job. 

So the Jewish people is not a race, and it is not, very simply, a religion — it is a conversation. It was [Scottish-born philosopher] Alasdair MacIntyre who said most beautifully that a tradition, when in working order, represents continuities of conflict. I loved that. So the Jewish conversation is real, but hasn't really been done. One of the things I've done in the last few years is to have public conversations with secular Jews such as Amos Oz, David Grossman, George Steiner and Stephen Pinker. I try, as far as possible, not to talk about Jewish unity, being "one", because manifestly we are not — we have religious differences and there's this huge split between religious Jews and secular Jews. But there is a Jewish conversation, in which each of us has a voice. The Jewish conversation is scored for many voices. There was a wonderful Rabbi called the Marharsha — Rabbi Shmuel Edeles, in the 16th to 17th century — who when told that every line of the Bible has 70 interpretations, said, "No — 600,000 interpretations." That is a kind of archetypal number, the number of adult male Jews who left Egypt, meaning that every Jew has his or her own unique interpretation of the Bible, and that is the Bible. We always believed in the written Torah and the oral Torah. The oral Torah is that conversation that has never ceased in 33 centuries.