Three Days at Jesus College, Cambridge

We stayed in my old college, Jesus College, first dedicated to St Radegund, the medieval French saint from Poitiers, and then, some 500 years later, to Jesus. It is famous for its chapel, begun in the 12th century and later restored by Pugin, William Morris and Burne-Jones: a grand ghost of a glorious past.

Walking into First Court, I remembered arriving there for the first time, lugging an enormous suitcase from the station and then along the long entrance passage known as the Chimney, which once separated the nuns from the town some 800 years ago.

I entered that ancient courtyard and saw, beside the old walls and cobbled paths, a lovely Tudor flower bed bright with primulas in the autumn sunshine. In one corner stood a very small, very old fruit tree, carefully propped up.

"How lovely," I remember thinking, "to take the trouble to preserve such a tree."

Across the courtyard are rooms once occupied by the poet Coleridge, who left Cambridge after running up considerable debts. His portrait now hangs proudly above the fireplace in the Senior Combination Room, where the dons gather for serious socialising after dinner.

Today the ancient green is dominated by a rather misshapen bronze horse by my old friend Barry Flanagan. I was present, in a sense, at its birth, in his great studio in an abandoned dog-food factory in the East End of London.

The vast space was dominated by a pony-sized figure of a horse being built up in layers of wet clay and covered with cloth. "You must never let the clay dry out," Barry explained.

It was a memorable evening. We smoked some strange substance in a long-stemmed pipe before eating a delicious meal in a Chinese restaurant. What remains in my memory is a haze of words and friendship. Barry later offered me a job, but I was still a serious scholar, deeply in love with teaching and immensely proud of my great class of 300 mixed-ability first-year students. I turned him down.

Returning to Cambridge all these years later stirred more difficult emotions too. I left this time in a fury of quite unaccustomed jealousy at the success of two former colleagues. One is now a well-known author on religion and science, a subject about which I feel very strongly; the other remains active as a serious scholar.

I had loved my own years as a researcher, but that part of my life ended after a breakdown when I was 35. For a few hours in Cambridge, surrounded again by the world I had once inhabited, I felt the loss of it very sharply.

Happily, the jealousy soon wore off when I returned home to Wiltshire.

One of the strongest memories of this visit is a sombre portrait of the great 16th-century Archbishop Thomas Cranmer hanging in the chapel. In my godless youth I had not even realised that he had been a Jesuan, as members of Jesus College are known.

Cranmer is remembered above all for his role in creating the Book of Common Prayer, whose language still forms part of Anglican worship today. He was eventually burnt at the stake during the reign of Mary I.

His portrait remains on the wall of the great college chapel, now only part of the size of the original medieval building. The chapel itself is extraordinarily beautiful, with vivid stained glass by Burne-Jones, richly coloured decoration associated with William Morris, and work by Pugin. Past and present seem to sit on top of one another everywhere in Cambridge.

That became particularly apparent as we walked through the college and saw signs announcing that the main hall was being used by Google DeepMind for dinner.

At breakfast the following morning there was an extraordinary mixture of people, with several different conferences and meetings taking place around us. We then walked through the ancient lanes, along Milton's Walk and past Christ's Pieces, beside the old walls of Christ's College. There is still said to be a mulberry tree there beneath which Milton liked to sit.

We were on our way to visit my former PhD supervisor. Having arrived early, I passed the time by looking him up on Google Scholar, which records academic publications and how often they have been cited by other researchers.

My wife suggested that I look myself up.

Rather to my surprise, there I was. My last academic paper, published when I was 70 and describing the teaching method I had developed, had received 62 citations.

I had never before looked to see what had become of my research papers. Sadly, as I had suspected, the paper I considered my best, and which had been well received at the time by those who understood the field, had received only three citations.

I had worked ferociously hard on that research. Eventually I suffered a breakdown from which, academically at least, I never really recovered. I had always taken teaching extremely seriously, but losing the ability to pursue research at the same level was a great sadness.

Yet perhaps something else came from it.

I began to write.

Over the years I have filled journals with more words, I calculate, than Proust wrote in À la recherche du temps perdu. If I am able to write poetry today, perhaps all those years of writing have something to do with it.

I spent nearly ten years at Cambridge as a student, researcher and fellow during the 1960s. Returning brought back memories of an extraordinarily intense period when I worked hard and played hard, made lifelong friends, encountered remarkable minds and established the foundations of my career.

We found my old teacher in good form, and talking to him brought another flood of memories.

We had both been pupils of the distinguished mathematician Philip Hall, who occupied rooms once associated with Maynard Keynes and decorated by Duncan Grant and Vanessa Bell. Hall would reminisce about tutoring Alan Turing and about Keynes and his motorbike.

Listening to Hall's advanced lectures was like listening to Schubert playing his latest compositions. Much of what he told us was new and unpublished, and the presentation itself was a work of art. He was a legendary figure and one of the fathers of modern British algebra. After his death his Cambridge chair passed to John Thompson, the celebrated American mathematician and one of the great mathematical minds of the 20th century.

To work among people of this calibre was intoxicating, but also daunting.

There is a particular technical skill required to do mathematics at that level, a mental agility perhaps comparable to the physical dexterity required of a great musician. I never believed that I truly possessed it. Yet I was intoxicated by the beauty and majesty of what these men could do.

Like Icarus, perhaps, I flew too near the sun.

Cambridge itself has changed almost beyond recognition. Approaching across the endless cornfields, you now see enormous developments rising from land that was once empty. Thousands of houses have appeared, while science and technology campuses spread around the edges of the old city.

When I was a student 60 years ago, development seemed almost impossible. Today Cambridge is an international powerhouse of science, technology and industry as well as scholarship.

And yet the Cambridge I remember is still there too: the ancient courts and chapels, the extraordinary minds, the friendships and rivalries, the excitement of ideas and the painful knowledge that brilliance does not always lead to happiness or success.

Three days back there reminded me of all of it.

A place wonderfully alive with achievement, memory, beauty and, inevitably, a certain amount of heartbreaking failure.