The great diaries of Samuel Pepys weren’t discovered until a couple of centuries after his death. He expected them to be read one day, or at least his biographer Claire Tomalin thinks so. But they could have easily not been found and never been read. Imagine the diarist carefully recording their life, assuming they’ve preserved their days, only for them to be so terribly mistaken? The actual fate of their diaries is not the cherishment of future generations, but the moth or the flame.

Pepys’s diaries were written in a shorthand of his own devising. The poor translator didn’t find the key left in the library, and spent years on them. He could have just as easily given up. And surely many have. The diaries written in code so they can’t be understood in the diarists’ life times. Or hidden in a secret place. Or the contemporary online diarist, using Penzu or WordPress and protecting their online journal with a password no-one will crack… ever. There’s the Christian singer Keith Green who wrote his diary on a computer thirty years ago; the entry he wrote before his plane crashed was corrupted on his computer. I think his widow, who wrote his biography, was convinced it would have been the most profound entry of all. And it is, because it’ll never be read.

What would be the ratio be of lost diaries? How many Pepyses were not discovered for the one which was? And this before we get to the great mass of ordinary diarists without a claim to particular literary merit. There would be less people mourning the loss of their diaries, but their lives may well have been lived as intensely, their existence as precious to them.

In my novel-in-progress, the Sinclair Morgan Library has an entire floor of diaries collected not just from public figures and soldiers, but from every ordinary person willing to donate their diary. Yet the backlog of unprocessed material has piled up; the collection is in disarray, and there may not be a home for them all in the newly corporatised library. I never make their fate clear, but I suspect some of them end up in the skip bins. The protagonist, Tom, was right to be suspicious when they asked school kids for their diaries back in the Bicentennial year.

Which is to say, there are many ways for diaries to be lost, and only a few for them to remain found.