Henry Allingham has earned his long rest. A hundred and thirteen years old, he survived Jutland and Ypres. Like many veterans he didn’t talk about it until, in extreme old age, he agreed to tell the rising generations about the comrades he lost. Thus this modest old engineer became a familiar figure, laying wreaths at Remembrance services and willing to talk to schoolchildren and reporters. His age made him a living monument: in a quiet hardworking life he saw three centuries, six monarchs and twenty prime ministers.

Tributes ranged from an honorary doctorate in his lifetime to a minute’s silence at Lords on Saturday. But perhaps the best tribute was that people listened to him. The boy who once longed to enlist lived to say on the BBC: “War is stupid. Nobody wins.” His descriptions of the men in the trenches standing, “pathetic”, before their expected death, are among the most moving we have.

Mr Allingham was listened to, which is not always the case with old people. But it should be. History does not lie only in books and journalism, but around us in nursing homes and granny flats. There is a healthy inclination these days to listen to WW2 veterans, whether home front or battlefront. One of the most educative weekends of my life was when we took an old farmworker, Dilly Sharp, back to Monte Cassino and heard of his terrifying teenage experiences. He refused to go on a “Battlefield Tour” because he heard there were lecturers: “Don’t want a bloody lecture, do I? I was there.”

As he led us round, we heard some things we were expecting — the hunger, the confusion. But also things we were not expecting: like the fact that he and his comrades didn’t resent the German soldiers — hungry boys like them — nearly as much as they hated the American bombers. Nor had we completely understood the brisk bathos of the way his war ended: demob suit and raincoat, civvy shoes, rail pass home to Darsham. No counselling, no suggestion of emotional support: back to your hoe, farm boy, and don’t upset people with horror stories.

The fascination of listening to the old is not just to “bring history alive” and confirm settled views of the past. The good bit is when they go off-message, quirky and human. I have never forgotten the day that an old lady’s casual remark revealed to my innocent schoolgirl ears her dislike of Churchill — “Horrid bossy man, all boiler suits and bombast”. It does not detract from Churchill, but it is liberating to encounter the stroppy, messy diversity of real experience. Not only wars need remembering: old people are excellent at puncturing all romantic ideas. My husband once found an original recipe for “Suffolk rusks”, and made them with curatorial care. A local septuagenarian said: “Ah, I remember these!” But as he glowed with pride, she put it aside and said: “My, we were poor in those days!” Retro rusks weren’t romantically better than modern biscuits. They were awful.

Sometimes the past, remembered sharply and realistically, has obvious lessons. Talk to anyone who has darned socks or saved for a rag-and-bone man, and you flinch with shame at our throwaway culture. Likewise, doing interviews about the preparations for D-Day I was struck by the dogged trustfulness of the thousands who laboured at unexplained tasks for a distant government — mystified builders making bits for floating harbours, schoolchildren packing small-arms in their lunch hour in a Hampshire gym and not being allowed to mention the activity, even to their parents.

Real memories nicely counterpoint any simplistic views of bygone mores. You think, for instance, that upper-class Edwardian girls were chaperoned innocents, their swains respectful? Well, a friend’s great-aunt Olive tells of a girl found one morning sewing up the traditional open front of her drawers. She blithely explained why: “I’m going out with Freddie in a punt.” Her virtue hung by those threads.

You think that before television, common people’s views of the world were laughably narrow? Find someone who ran a miners’ philosophical society, or meet an old lady in Suffolk whose husband ran a profitable private lending library. He took a van round the villages, stuffed with classics and factual books as well as light reading. It made him a good living until TV killed it dead.

Biographers often find unexpected details, but there is something special about random memories from contemporaries. It is good to learn, as I did at the weekend, that younger household members clearly recall Ludwig Wittgenstein taking time off from the Tractatus Logico- Philosophicus by lying on his bed all day reading Zane Grey westerns. It is instructive, though sad, to chat with a 100-year-old suffragette and have her casually remember turning down marriage with a man she adored because it would have ended her teaching career. “One couldn’t have both, dear. Not like girls now.” In an age where ex-prime ministers (well, the last one anyway) display a sense of pampered entitlement to luxury, cherish also the Dowager Duchess of Devonshire’s story of Alec Douglas-Home. Coming home from the Kennedy funeral, he offered to lie very still in his pyjamas in the Chatsworth guest bed and not rumple it, so they wouldn’t have to change the sheets for Princess Margaret the next night.

The voices of earlier generations also remind us that our narrow consensus of modern wisdom is not all that there is. We need to know what awful things were done and said — to children, to the mentally ill or disabled, to ethnic minorities — by people who were just as well meaning as us. We need to know what hardships and sorrows were silently borne. We should learn not only what was written down, but what was felt and thought by the unrecorded many.

Even I, in my fifties, can astonish modern students by recalling how an overdraft of a few pounds used to get you called in and shamed by your bank manager (invariably with a string vest showing through a drip-dry Tricel shirt). Or that it was considered shocking when 1970s supermarkets began accepting Visa cards for groceries. And only conversations with elders can remind us of the fabulous but untried newness of things: in Canada, I once met a man whose father rode the first cross-continental train to get a job building a new place called — er — Vancouver.

Yes, listen to that greyhead in the corner. History is human.

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