© Luke Waller

Last weekend I was at the Hay Festival to give the annual Eric Hobsbawm Lecture. My subject was the way in which individual lives can inform historical analysis and change great moments in history. The theme generated lively exchanges at a fine lunch hosted by Eric’s widow Marlene.

One invitee, film-maker Revel Guest, told us how she had once filmed the US writer James Baldwin with his naked assistant — something that the BBC decided not to use in a film now lost. Another, Elizabeth Bingham, widow of Thomas, the law lord who did more than anyone to safeguard Britain from lawlessness in the years after 9/11, revealed that it was she who was the unidentified female candidate rejected for membership of the all-male Travellers Club in London a couple of years ago — an incident that led one prominent member, a certain Justin Welby, to give up his own membership.

Later I take part in a radio discussion with Harry Parker, the soldier-turned-author who lost both legs to an improvised explosive device in Afghanistan, war correspondent Janine di Giovanni, and former CIA supremo Michael Hayden — who is surely the only person at Hay who thinks waterboarding is not torture and that former President George W Bush shouldn’t be prosecuted for it.

The conversation is convivial, not hostile, but Janine and I feel impelled to gang up on Michael when he says that the Abu Ghraib photos shouldn’t have been published. He is against transparency and in favour of something called “translucency”. As he says this, I wonder whether the windows in his home are plain or frosted glass, but decide not to inquire.

In the course of a conversation about the South China Sea dispute between the Philippines (for whom I act) and China, I glean one useful snippet of information from the world’s former No 1 spy: if you don’t want the Chinese or anyone else to listen in, use WhatsApp, still impenetrably encrypted.

I am hopeless with faces and names, which proves to be a source of constant anxiety at public events. “How exactly do you spell the name you’d like me to inscribe?” tends to work at a book signing when I am confronted with a vaguely familiar face whose name I struggle to remember, but backfires spectacularly if the dedicatee is a Liz or Charles.

At an event in London earlier this week, it was a relief to reach the part where I could make a few remarks. I took the opportunity to express, very publicly, feelings of fraternal love towards my brother, who has put up with years of queries about obscure family memories for things I’ve written.

Later, over dinner at nearby Fischer’s — where the Wiener schnitzel wins out over all competition — he thanks me for my nice words, then asks whether there was a particular reason he got no mention in the acknowledgments for my latest book. I want to set him straight, but am unable to do so after leafing through the relevant pages. Aghast, I immediately email my publishers with a corrective insert, extolling the virtues of “my brilliant brother Marc, the finest”. Knopf in New York replies, asking if he is my only brother. “This information affects whether to use restrictive or non-restrictive commas,” they explain. I take an instant decision not to consult our father.

The Hay lecture goes well — apart from a glitch with the PowerPoint, as Apple decides that the right moment to invite me to upgrade my software is just when the screen is being looked at by an audience of hundreds.

I argue that once again a poisonous nationalism is coursing its way through the veins of Europe, and here in Britain the noxious odour of identity politics is in the air, as the two former mayors of London invoke Adolf Hitler — one to argue that the Führer was actually an early supporter of Zionist Jews, the other to suggest that his aims were in some way shared by the EU. It is offensive nonsense of both kinds that seem to be propelling us to a gloomier place, as groups are lumped together in blatant disregard of history, a path that, if followed, will surely consign us to a very dark corner, a sort of race back to the 1930s.

Nevertheless, lightness triumphs in the end. At a party that evening, a friend commends me on the lecture I have delivered. “Superb,” he says. “Your grasp of science is astonishing, and so is your sense of what we can and cannot know.” Somewhat perplexed, as I barely passed any science O-level, I inquire further. Like me, it seems, he can’t tell one face from another, or indeed one lecturer from another, for he has confused me with the professor of Public Understanding of Science at the University of Oxford, who had delivered a parallel but rather different talk in the tent next door.

Philippe Sands QC is professor of law at University College London. His book ‘East West Street: On the Origins of Genocide and Crimes against Humanity’ is published by Alfred Knopf (US)

Illustration by Luke Waller

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