I find it hard to throw things away. Old Chelsea FC match programmes, a champagne cork from my 50th birthday, a Christmas card sent to me more than a decade ago by the Secretary of State for Transport, a ticket to see Paul McCartney at the O2, a copy of the JC announcing the birth of a member of my extended family, an invitation to the bar mitzvah of the child of someone I haven’t seen for five years.

To these, add things I have deliberately bought in order to keep. A collection of letters written by prime ministers, for example, which I began when I was reading a biography of each one. And the books, of course, don’t forget them. Thousands of books, mainly history and politics, kept in check only by using a Kindle to keep some of the more recently published volumes.

Working on the memoir of my parents that is shortly to be published (Hitler, Stalin, Mum and Dad: A Family Memoir of Miraculous Survival), I have realised two things. The first is that my habit is inherited.

I had always known that my maternal grandfather, Alfred Wiener, liked to keep things, especially books. My mother used to recount seeing him off on a book-shopping trip and sighing with relief when he returned in a cab with a single carrier bag. Only for another taxi to pull up, this one with all the books in it. I had fondly imagined this story to be Mum’s little joke. But as I learned more about Alfred, I understood it was just what had actually happened.

Keeping things had been his profession. The main weapon of his war against fascism had been his collection of everything that the Nazis published and a record of all they had done and said. The Wiener Holocaust Library (thriving still in Russell Square) became the world’s leading centre of documentation of the Nazis.

Nevertheless, the extent, the thoroughness, of my family’s collecting habit startled me when I set out to tell their story. Not simply momentous documents — the piece of paper telling the family that they were to be sent to Belsen, for instance, or the last letter of my great aunt before she was sent to Sobibor — these anyone might keep. But little things. An old passport, long expired. Or the dining room coupons from the liner that took my mother and her sisters on the last leg of the journey from Belsen to New York. Or the letters congratulating Alfred on his daughter’s engagement.

So by keeping these little things from my own life, I am merely maintaining family tradition, staying true to my inheritance.

The second thing I realise is how valuable these relics are. The Wiener Holocaust Library was vital to the Nuremberg trials and remains a unique and important resource. It has certainly brought home to me how extraordinarily important it remains as a record of the Holocaust, as is the wonderful Refugee Voices project of the Association of Jewish Refugees. Without their recording of my father’s story, a four-hour interview, I am not at all sure that my book would have been possible.

These projects need our support. After the war, my grandfather found it hard to get support for his work, with many people openly wondering what the point was. They don’t wonder now.

But as well as requiring our support, I think they should also inspire our emulation.
Of course, I am not typical. Not everyone is writing a book on their family. My own cruise dining ticket is unlikely to aid the production of a hardback sometime in the future.

Yet nevertheless, you realise how the little things build a bigger picture of life. From an old passport you might be able to learn someone’s height, or who they considered their next of kin, or where they travelled for business and pleasure. From their old programmes and tickets you learn of their activities. From their old invitations you learn of their friends. From their stamp albums or autograph books you learn of their passions.

And when you are gone, your family will want to know these things about you, to be reminded of you.

They aren’t a pile of junk, even if they look like a pile of junk. Or at least that’s what I tell my wife.

‘Hitler, Stalin, Mum and Dad: A Family Memoir of Miraculous Survival’ is published on June 8