John Sutherland: I was depressed. I was a drunk. I was cured. It worked for me. But would it work for you?

Do you medicate Sylvia Plath in her last two years and lose 'Ariel'?

The very term "mental health" raises a number of questions. A healthy mind in a healthy body is the ideal, according to Juvenal's dictum,... mens sana in corpore sano. If only this were as simple to achieve as to define. While it is relatively easy to identify physical well-being ("My word, you do look well!") the other kind - health in the head - is more difficult to identify, even paradoxical.

Try the following quiz. You are Master / Mistress of the Universe. The quality of cultural life that universe supports will be changed by your MoU powers. Be wise.

1. Do you medicate Sylvia Plath in the last two years of her life and stave off her terminal depression, her suicide - and most of Ariel?

2. Do you then get Mr and Mrs Ted Hughes into marriage counselling, successfully, and forgo Crow?

3. Ditto Kurt and Courtney and lose, for posterity, a load of grunge?

4. Do you get Dylan Thomas into a "program" (the Priory, Hazelden, whatever) early in his drinking career and ensure that, like the other Dylan, the Welsh dipso-bard makes it to 60 and a "late phase"?

5. Ditto George Best, and preserve him to play for ManU and Northern Ireland for 10 years.

6. Ditto Scott Fitzgerald, lose Tender is the Night but get another 20 years of not very wonderful fiction.

7. A quiet young American makes an appointment with Jung in Switzerland, in 1919. His marriage has broken up, he's depressed and suicidal and the post-war world is driving him crazy. Cure means you missThe Waste Land. A good deal?

8. Do you imprison Pete Doherty in Denmark, which has, we're told, the best rehabilitation record in the world? Cleaned-up Pete? Do we really want that?

9. Ditto Robert Downey Jr, George Michael and whichever other celebrities are being thrown to the lions this season.

10. Do you withdraw Alan Turing, the father of the computer, from the court-enforced chemical "cure" for his mental "disease" - homosexuality - in the interest of the digital revolution?

My guess is any MoU, on World Mental Health Day on Tuesday, would weigh up each of these situations differently. Tricky doesn't come into it.

As the above quiz tendentiously suggests, the borderline between mental health and creativity, as Stephen Fry has recently been exploring - by the dazzling incandescence of his own ego - is a blurry one. You have a Jacobean playwright. His only son, Hamnet, has died: his marriage is unhappy. The mood of the time is low, after the Elizabethan heyday. The result: four great (but profoundly depressed and depressing) tragedies. Are they the products of temporary mental collapse (easily relieved with a course of Prozac), or of that supreme condition of mental health which we call genius?

Then there is the 12-year-old whose shiftless parents have put him to work in a filthy blacking factory by Hungerford Stairs. It's child abuse and certain to lead to lifelong trauma. He's rescued by 19th-century social services, put in care, with, thank God, the prospect of a "normal" life ahead of him. Congratulations, health workers. You've just written off David Copperfield.

The Turing example should, I think, give us particular pause. We should be humble in assuming that our therapies, whatever stage scientific knowledge may have reached, can do what we think they can do. It is to me strange, for example, that Stockholm has never seen fit to withdraw, retroactively, the Nobel Prize it awarded Egas Moniz, in 1949. Moniz invented prefrontal lobotomy. He was, the committee said, "a wonderful man". Many, then, might have agreed. Now, few would.

The operation, which involved scooping lumps out of the brain, as if it were ice-cream, was subsequently popularised in the US by Walter Freeman who trundled round in his "lobotomobile", demonstrating his "ice pick and hammer technique" to any hospital that would let him in, and knocking off 10 ops a day in hotel rooms. Nothing could stop his campaign to make America mentally "healthier".

It would be a commendable act of humility, and an admission that mental health is difficult to define and fiendishly difficult to manufacture, were Stockholm to respectfully rescind that award to Moniz.

The mental health condition most worryingly widespread in the UK today is alcohol abuse. One in 10 of the population is considered to be alcoholic, pre-alcoholic, or recovering alcoholic. I speak as one in the third category. Alcoholism typically proceeds from a mental disorder (in my case, depression) and goes on to precipitate a whole range of secondary health problems (in my case, acute depression). Whether alcoholism is a mental disease is a fraught question. All I can say is that it felt like one.

The pioneer proponent of the disease concept of alcoholism, Elvin Jellinek, defined it as complex in origin. There are, as any pub clientele will confirm, different kinds of alcoholic: the occasional or binge drinker, the chronic soak, the symptomatic drinker. What they have in common is that they "overindulge", until they're as overindulged as newts, and then they ruin their lives and the lives of others.

I tried a number of remedies before achieving sobriety. For example, the pharmaceutical nostrum - Antabuse. But I drank through the pills and even came to enjoy the violent physical reaction. I also went the psychiatric route. It compounded my depression more than booze - waiting three hours for a half-hour session with an overworked white coat who had to look at his notes to remember my name.

I finally got sober in Alcoholics Anonymous. AA groups differ, but if you're lucky enough to find a good one you discover something rather striking. Some recovering alcoholics are grateful for what they have endured, and regard it, to be corny, as a learning process. It has matured them. It has been painful, but they cannot entirely regret it, or wish that it had never happened. Not everyone feels that way. I did.

Of course everything should be done to promote mental health. In the vast majority of cases the therapies we have should be energetically applied. But we should also be aware of the blurriness - the Fry factor. In some cases, a wise Master of the Universe would intervene with caution, or, perhaps, not at all. Remember Freeman's icepick. Remember Hamlet.

John Sutherland is Lord Northcliffe Professor Emeritus at University College London