What makes a book a Jewish book? Does it have to be a book by a Jew, or can it simply be about Jews? Does it have to be a book by one person, but with two opinions, and perhaps three cars? Or, could it be a fairly universal book, of equal interest to all, but merely with a Jew in it? Page 173: a door opens, enter a man in a yarmulke. Is that enough?
For the past few months, along with my fellow judges on the Jewish Quarterly-Wingate Literary Prize, these are the questions I have been trying to answer. Needless to say, we have read many, many books. All have been discussed over sandwiches at JW3. There are four judges, and only three Jews, but between us all we have sometimes held as many as nine or 15 opinions at a single time. Never yet have we done a tally of cars, but this is a literary prize, so we probably all ride bikes.
By necessity, it is has been a process of some self-examination, too. For, one thing on which Jews - and not just Jews - have many, many opinions is the question of what being Jewish (or sometimes just Jewish-ish) actually means.
Samantha Ellis, our chair , is a playwright and a writer, who is Iraqi Jewish. Rabbi Jonathan Wittenberg is a theologian and a scholar, embedded in British Jewish life. Tahmima Anam is a novelist and columnist, originally from Bangladesh and, as a result, may have a clearer perspective on British Jews than any of us. And then there's me, a thoroughly secular journalist, and not just Jewish-ish but also Scottish-ish and posh-ish, too. This is not the first book prize I have judged, but never before has the question of who I am seemed quite so relevant to what I thought. At times, there has been angst, but enjoyable angst. Which, I suppose, is as Jewish as anything.
Certainly, there have been themes. Quite a few of the books we have read, for example, have been about the Holocaust. Two of the excellent books on our shortlist are academic studies of that period: Nikolaus Wachsmann's peerlessly researched KL, and Dan Stone's thoroughly eye-opening The Liberation Of The Camps. Several others have the Holocaust as a backdrop, which is of course unsurprising, but still provokes some reflection. All Jews are interested in the Holocaust, probably, but does that mean all books about the Holocaust are Jewish books?
One of my favourite books that did not make the shortlist (if "favourite" is not the wrong word, and it almost certainly is) was The Zone of Interest, by Martin Amis; a horrifying and visceral novel set in Auschwitz and told largely from the perspective of a Nazi.
While Jews may perhaps be disproportionately interested in reading such a novel, we still concluded (I think unanimously) that it was not, in any way, a Jewish book, nor a suitable candidate for such a prize. Even though, it seems safe to say, it almost certainly wouldn't get a Nazi book prize, either.
Then there were the books about Israel. Our shortlist includes Claire Hajaj's beautiful Ishmael's Oranges, which is certainly a novel about Israel but also about Jews, and Palestinians, and, at times, what it means for both to be in a country such as Britain, looking back.
Others, though, were simply Israeli books, about Israel, and perhaps by Israelis, too. Wonderful or not, should a British, Jewish book prize go to such a book? Is Israel always a facet of the British Jewish experience? Even when Israelis are writing about Israel, and giving us no thought at all?
Biographies were easier. Our shortlist contains two: The Life of Saul Bellow by Zachary Leader and The Impossible Exile by George Prochnik, about Stefan Zweig. The former is a vast literary achievement and, in the end, if Saul Bellow wasn't writing Jewish books, then who the hell ever was? The latter is as much a meditation on exile itself as it is a portrait of its subject.
Inevitably, we sometimes thought of community politics. Between Gods, by Alison Pick, is the only memoir on our shortlist. Although also not British (she's Canadian) it is a deep portrait of a wholly familiar diaspora community. Most of all, though, it is a book about conversion; one of those half-addressed and sometimes uncomfortable crevasses of Jewish experience into which new literature can help map a path. Howard Jacobson's novel J, meanwhile, is a dystopian projection of the swelling British antisemitism so many of us dread. Both of these books are powerful statements. Whether that's our intention or not, perhaps shortlisting them is one, too.
Such were the considerations that made judging this prize such a fascinating, complex experience. As with the judges of other prizes - the Baileys Prize, the Man Booker Prize - we knew that our task was to pick the best, eligible book.
Unlike most other prizes, however, the whole concept of eligibility was a judgment in itself. Another panel may, of course, have come to other views. We, though, became increasingly clear that we were judging not only merit (although without great merit, of course, no book had a hope), but also something else.
I cannot speak for my fellow judges on this, but for me, the relevance has been profound.
Stories of smashed communities throughout the 20th century have made me reflect on how unusual the British Jewish experience sometimes is, with this country alone in Europe being home to communities - such as my own, in Edinburgh - that survived intact.
Simultaneously, stories of cultured, polyglot exiles walking the earth have made me think of my mother's Polish family, who were exactly that.
Reading about old hatreds, side by side with the fears of new ones, have helped me to understand both. And yet, at the same time, the picture has been far from universally negative. Exile and displacement are not the only Jewish story, and nor are they just a Jewish story.
Today, our community is fortunate enough to reflect on all of this in some comfort. Could it be that the descendants of today's exiles, from so many horrible contemporary conflicts, will one day be able to do the same? Speaking as a writer, part of me now feels the urge to fill the holes in our shortlist; to address the sense of truly having roots in this country, and truly belonging to it, which so many British Jews, at least in my experience, truly feel.
At the time of writing, anyway, we do not yet have a winner. Nor even a secret likely one, in part because many of these questions, while raised, remain unanswered.
Still, we have one last meeting to come, bringing our many opinions - and our many sandwiches - to the table. A friend once told me that there is really only one Jewish story, which has been repeated for millennia, and goes, "they tried to kill us, we're still here, let's eat". But she, I now realise, was quite wrong. They are legion. Whichever book wins, you should read them all.
The winner of the 2016 Jewish Quarterly Wingate literary prize will be announced on March 14.
To find out more visit www.jewishquarterly.org.