The Extract: Dr Jonathan Miller chooses between science and showbiz

A new biography reveals how, and why, the theatre and opera director made the 'wrong' choice in 1960

In Edinburgh, word spread like wildfire about a new revue subverting sacred cows, blitzing the status quo. The city's Evening News proclaimed Beyond the Fringe to be the Festival's hottest show and started printing highlights from the script. After a thinly attended first night, queues formed round the block and each performance was crammed to 140 per cent capacity with feverishly applauding spectators, some jumping on their seats and hurling their coats in the air.

Jonathan Miller and Peter Cook continued to improvise and make each other corpse with laughter, yet they won all the more fans with their informality. Alan Bennett believes Beyond the Fringe was daring and intimate in a new way because, as he says, "We dealt with things that young people made jokes about in private but never publicly".

It was as if the Fringers – as they came to be known – were almost literally at home onstage, or the theatre was some Oxbridge Junior Common Room suddenly open to all. This made the audience feel simultaneously at ease, privileged and mentally stimulated. The lack of professionalism generated moments of utterly unplanned hilarity as well, not least when Dudley Moore was meant to be playing the National Anthem in the opening sketch and didn't realize that the others had got started. He was duly heard, by a hushed full-house, as he wandered around offstage, whistling and flushing the loo.

A letter that Miller wrote in September and posted off to his St Paul's School friend Oliver Sacks (by then in America) conveys what a roller-coaster those festival weeks were, propelling him from nervous pessimism to elated crowing. Apologising for the delayed correspondence, he explained: "It is now a month since I went up to Edinburgh and a lot has happened as a result of that excursion… We settled down to a strange week of rehearsal, rewriting and hangdog prognoses of our forthcoming failure… After the first night the critics gave us fantastic notices and shortly the cast of the Old Vic [performing in rep with the Fringers at the Lyceum] were standing at the back of the auditorium to see us. Within a week half a dozen West End managements were after us… The fees which we are to be paid [for the London run] are astronomical… If the show is successful we shall almost surely come to Broadway some time at the beginning of 1962."

He retrospectively calls the Lyceum run "a cocaine-like snort of celebrity and approval", and his letter reveals that the whole transfer package, including New York, was being planned much sooner than some accounts of Beyond the Fringe suggest. Nevertheless, in the immediate whirl of Edinburgh, the spiralling excitement spelled disaster for his progress as a doctor. Cook and Moore were keen to transfer to London as soon as possible. They regarded any shilly-shallying from their co-stars as ridiculous. Miller, though, was on the horns of a major dilemma. He had managed to take a fortnight's leave to coincide with the Festival, but no hospital was going to employ a house officer who transformed into a revue artist every night. Such an open relationship was unacceptable. He could not both walk the wards and tread the boards.

When his wife Rachel came up to Scotland, the two of them ended up pacing round and round Castle Rock until dawn, with Miller in crisis, unable to make up his mind. He calls it "that fatal night", noting that Rachel rightly foresaw how there would be no return from this runaway hit if he signed up for the West End. "But", he adds, "she knew that I wanted, in some ways, to go on with Beyond the Fringe." Perhaps whichever choice he made, he would never forgive himself.

In his September missive to Sacks, he was still clinging to the idea of attaining medical goals, though wishful thinking had begun to creep in as he wrote: "I was involved in the old dichotomy [as regards the West End deal]. This time however I have decided differently. I have decided to abbreviate my stay in Cambridge [holding down a new post at Addenbrooke's Hospital] to six months. I shall then give up Medicine for a year whilst the show plays in London… At last I am beginning to see the possibilities of what I have always regarded as an ideal situation viz. Medicine as a delightful hobby, as opposed to an irksome breadwinning slavery."

In practice (or rather, out of it), he would never write a second paper for the Lancet, let alone win a Nobel Prize for neurology as his university friends had envisaged. At some point, he must have recalled Danny Kaye's galling personal prediction, "You'll never do it", or indeed Kaye's screen character, Walter Mitty, who merely daydreamed of being a top surgeon. How ironic too that, after converting Rachel, the child ballerina, to medicine, he himself should caper off into what he calls "this footling flibbertigibbet world of theatre" while she became a long-standing GP.

Far from disgraced, he is part of a historic line of trainee and qualified doctors who have migrated into comedy and drama: Oliver Goldsmith, Schiller, Chekhov, Ibsen, Strindberg, William Carlos Williams (who wrote some plays as well as poetry), Somerset Maugham, Christopher Isherwood, Mikhail Bulgakov, and more recently Michael Crichton (of ER). Other physicians-turned-humourists have included Monty Python's Graham Chapman (who went to Cambridge to read medicine because he saw Miller in Footlights), Graeme Garden of the Goodies and Harry Hill.

Regardless of that, Miller views medicine as his lost ideal and comedy as his tragic fall, a woeful degeneration, certainly not progressive evolution. Often he talks of his lapsed state as if it resulted from an accident, a stroke of ill fortune. He compares his career change to being "tripped up" by showbusiness, to suddenly "falling out of an aeroplane", to "stepping off the edge of a diving board into this murky swimming pool where my moral fibre rotted irreversibly". He makes this sound like a Wittgensteinian case of "My foot went out" as distinct from "I moved my foot", and his CV looks like a case of Chinese whispers, of unintentional typos or slips of the tongue, recategorizing the medic as comic, the doctor as director, and sliding from the operating theatre to opera and theatre.

He will admit to a degree of self-determination, observing: "You make a small choice and find it's committed you to a large change of life." In an upbeat mood, he will confess that he had great fun and remains proud of Beyond the Fringe. Even so, that never cancels out the remorse. "I still," he concludes, "fiercely regret the distraction. I think that was a bad thing I did." In spite of his theory of comedy – that laughter is generated by sudden wrong categorizations – his own reclassification, swapping professions, has left him down in the mouth.

The "irksome breadwinning slavery", alluded to in his letter to Sacks, had also played a part. He was no longer enamoured with the medical profession because he felt it didn't embrace its youngsters with any warmth. John Bassett [who had invited Miller to co-create Beyond the Fringe] had caught him at a low point, just as he was facing hard graft as a junior doctor: extended periods of separation from Rachel, exhausting working hours, and what he considered an obstructive geriarchy.

It was not institutional anti-Semitism, as in his father's era, but it was ageism of the old-school variety, whippersnappers being put through the mill by their elders. He was enticed by the comparative ease, glamour and adoring applause of a life in the theatre. Sociologists were, moreover, predicting that the future lay in the cultivation of leisure. With more spending power and mod cons in the pipeline, Britain was going to become a Utopia of free time and frivolities, with the arts and entertainment in the ascendant.

After the heady success of Edinburgh, Miller told Sacks: "I now for the first time in my life actually don't give a fuck for what anyone in the [medical] profession thinks." Being turned down for a registrar's post in neuropathology at the National Hospital for Nervous Diseases, in London's Queen's Square, had riled him, no doubt. One of his University College friends was working there and asked the senior neuropathologist why such a superlative graduate had not been appointed. "No, no, totally out of the question," came the reactionary reply. "He turned up wearing a sports jacket."

Miller did go to Addenbrooke's, and he worked at both the London Hospital and the Royal Marsden during the West End run of Beyond the Fringe. However, this only intensified his misery because, on bad advice, he chose to study general pathology and neuropathology, before getting down to neurology itself. As a resident assistant pathologist at Addenbrooke's, his dull task was to cross-match blood for transfusions. At the London he did autopsies, and at the Marsden he took a mind-numbing job, freezing cancer cells, unpaid. He was faced with a prospect of exasperating years before he could really investigate how the brain affects behaviour, and he lacked the patience for that. "It was," he says, "a complete cock-up, absolute folly, and I knew I was up a gum tree."

The only perk regarding Cambridge was that some old associates were still in town and Rachel briefly came to Addenbrooke's to train in obstetrics. In a winter letter to Sacks, he described her as wonderfully replete with domestic comforts – rugs, warm towels, hot baths, smiles and chocolate. That aside, he went on: "I have now been working for six weeks and am still very uncertain if this is really what I want to do… I am very relieved that I have the escape clause of the revue in April."

A follow-up letter, veering between self-rebuke and self-regard, went further: "Alas, I think it is all a literary illusion… The dancing mote under the microscope is all very well until you have to sit over it hour after hour… It has happened to all of us [the gang from St Paul's] lured into biology by the [Edmund] Gossian flavours of the subject…. You… Eric [Korn]… Our love of science is utterly literary… I do not think that I will ever do experimental work of any value, if indeed any at all."

Incidentally, Sacks's prospects were less rosy than Miller's at this point. He had, as yet, won no public recognition and was living dangerously in a leather-clad biker phase in California, donning a white coat by day but going wild at night, taking what he himself describes as "a fair sampling" of LSD. Convinced that he would die young, he posted off to Miller, in 1960, a sealed package inside which lay a kind of will and testament in waiting:

Dear Jonathan,

I hope you will never read this note, but if you do you can do me a last favour. This box contains a selection of what I have written over the years, and if I have ever written anything of worth it is likely to be here. I leave it to your good sense and discretion to retrieve anything you think fit, destroy, or keep as a memento.

Love, Oliver

Among the selected scripts was – crucially, as it turned out – a draft of Awakenings. This record of Sacks's extraordinary work with L-DOPA and with patients suffering from post-encephalitic Parkinsonism was, eventually, going to make him world-famous.

This is an edited extract from Kate Bassett's 'In Two Minds: a biography of Jonathan Miller', published by Oberon Books. Copyright Kate Bassett