Mankurt, however, is no part of mat. Mankurt is a word of Central Asian origin which means, roughly, ‘slave’.

I came across the word for the first time as an undergraduate when I read Chingiz Aitmatov’s long novel The Day Lasts Longer than a Hundred Years, which is a strange blend of science fiction, socialist realism and Kirghiz folklore. One of its key elements is the legend of the mankurt.

The mankurts Aitmatov describes are prisoners who have been captured in battle and subjected to a bizarre and degrading cryptoscientific procedure. Their heads are shaved and the skin from a camel’s udder is fastened to their naked scalps. The men are manacled and fitted with collars to prevent them removing the grafts either with their hands or by rubbing their heads on the ground. They are then left in an isolated place on the steppe in the baking summer sun. Most of the victims of this process die, but in those cases where the graft takes hold, the men lose their memory and identity to the point where they become robotically obedient, a kind of steppe golem.

In Aitmatov’s book, the process is described in great detail. Clearly, it has no scientific validity, but Aitmatov makes the legend function as a veiled criticism of the Soviet suppression of Central Asian culture. The mankurt is, by metaphoric extension, the person who has lost touch with his own cultural origins.

I didn’t imagine that Misha Bykov was using the word to express such a complicated idea. I took it to mean something more simply disparaging, like one of those discredited categories of human intelligence that only survive as insults: moron, imbecile, cretin. And I understood why Vera would have bridled at his remark.

But all the same, I couldn’t help thinking of the awful image it evoked. And it left me with a lingering sense of disquiet.

*

Over the succeeding weeks, I visited Vera and Jack about half a dozen times. On each occasion, I found a different pretext to drop round: I brought a copy of Pilgrim’s Progress the first time, then a brass-tipped calligraphic pen and some ink. The third time I brought Vera some chocolates and an inscribed copy of my Augustan satire book. She seemed genuinely touched by the gift.

Gradually, Vera opened up to me. I suppose I must have flirted with her a little to begin with, but she seemed immune to that variety of flattery: Vera was an intellectual snob. She boasted that five generations of intellectuals preceded her on both sides of her family. Her father was Lithuanian, she told me; her mother Jewish. She had a sister in Perm who was a gifted pianist. I told her about Leonora. In retrospect, I think I may have shared more than I intended about the state of our marriage.

I found her compelling company. What you got with Vera was either melodrama or fierce intelligence, sometimes both at the same time; she had no capacity for or interest in small-talk. She would have been exhausting to live with, but it made a refreshing change from the glib and shallow irony that was the dominant note of my interactions with colleagues and students. The week after I gave her the satire book, she took issue forcefully with a number of the assertions I’d made in the chapter on Swift. I’d have to say she was largely right.

She was very rough in argument. I like an intellectual scrap myself, and I found it stimulating too, but not, I think, in the way she did. It was intimate and almost physical. Once or twice, after fierce disputes – none of which I won – I remember her staring at me, her eyes very bright, her face flushed and her upper body moving very slightly in time with her breath.

One of her particular interests was Ada Lovelace, Byron’s bluestocking daughter and pioneer computer programmer, who once lived in a house on St James’s Square. Vera spent about two hours one afternoon trying to make me appreciate the elegance of Lovelace’s procedure for calculating Bernoulli numbers.

I pleaded with her, telling her, only half-jokingly, that her explanation was wasted on an arts graduate.

She looked thunderous. I had hit some intellectual sore point. ‘Don’t be proud of this false specialisation that is killing wisdom,’ she said. ‘There is no natural distinction between the arts and sciences.’

‘Well, one deals in facts,’ I said. ‘The other doesn’t.’

‘So history is an art or a science?’ she countered. Before I could reply, she added: ‘Tolstoy and Dostoevsky have also discovered the laws of nature!’

‘They were novelists, Vera. By definition, they made things up.’

‘You are so limited! Bill Gates also makes things up. Is he a novelist? Science, it’s a process of creation too. Literature itself is a species of code. You line up symbols and create a simulacrum of life.’

She was now breathless with excitement and talking so loudly that I worried someone would hear us. She took a step towards me. ‘Close your eyes!’ she commanded.

Her tone was so peremptory that my instinct was to refuse. She must have realised, because she said it again, this time softening her voice, making it into a request.

I looked at her. She nodded. I closed my eyes.

‘The bulrushes waved at the side of the river,’ she said. She spoke very slowly. It reminded me of when Leonora would practise one of her pieces largo, and the way the pulse of it would fill the house. ‘A bee moved lazily among them. The small child slept in the basket of reeds. On the bank sat a woman, curling a ringlet around her ear.’

I was still a little overexcited from our argument, and it took a moment for my mind to slow down and match Vera’s delivery, but as it did a strange thing happened. It was as though a complex flavour began to unfold in my mind. There was a distinct sequence of changes. First, that initial resistance, then a feeling of relaxing, joining to the stream of her words, and the sensation that they had taken over the image-making centres of my brain. I saw the fat, brown heads of the bulrushes, heard the bee. Then I felt the sun overhead – which she hadn’t mentioned – and I knew that the woman’s shawl was blue.

Vera stopped. There was for a moment such peace in my inner world that I didn’t want to open my eyes.

*

Another level of intimacy was reached on the day when Vera finally condescended to speak to me in Russian. I had wondered if I would glimpse a little more of the real Vera when she spoke in her native language, but my Russian wasn’t good enough to intuit anything profound from her squeaky Moscow accent and when she spoke quickly I could barely follow her at all.

Whenever the conversation returned to Jack, she seemed to deflate a little. It was odd, I remember thinking at the time, because she had had his whole life to reconcile herself to his strangeness.

After the first visit, she always found some excuse to keep me away from him: he was sleeping, or poorly, or irascible. But my attentions must have gradually worn her down. The fourth or fifth time I turned up, I brought with me an engraving of Streatham Place, the Thrales’ mansion (now demolished), which I’d bought from a Cecil Court dealer about ten years earlier and though she warned me he was feverish, she consented to my giving it to him in person.

We found him asleep on his bed. At Vera’s suggestion, I called out ‘Jack’ to him until he opened his eyes. He gazed blankly at me for a second.

‘Jack. It’s me. Remember?’ And then, because he clearly didn’t, I mentioned the poem that had provoked his reaction on our first encounter. ‘Remember? “Lycidas”?’

As soon as it was out of my mouth, the word seemed to work on him like Open Sesame. There was a deep, chthonic rumble in his vast chest, as though the door to a tomb was opening. His eyes widened. He echoed me in a low, sonorous voice, half swallowing the sibilants of the name: Lyshidash.