Health, says the WHO, is a state of complete physical, mental and social wellbeing and not merely the absence of disease or infirmity. But could it be that some sort of infirmity is essential for being healthy?

We are used to the idea that to understand light we must know darkness. Is it poetic conceit to think that it must be the same with health? William James, the father of psychology and brother of novelist Henry, was clear on the value of infirmities:

Few of us are not in some way infirm, or even diseased; and our very infirmities help us unexpectedly. In this temperament we have the emotionality which is the sine qua non of moral perception; we have its intensity and the tendency to emphasise which are the essence of practical moral vigour; and we have the love of metaphysics and mysticism which carry one’s interests beyond the surface of the sensible world. What, then, is more natural than that this temperament should introduce one to religious truth, the corners of the universe, which your robust Philistine type of nervous system, forever offering its biceps to be felt, thumping its breast, and thanking Heaven that it hasn’t a single morbid fibre in its composition, would be sure to hide forever from its self-satisfied possessors? If there were such a thing as inspiration from a higher realm, it might well be that the neurotic temperament would furnish the chief condition of the requisite receptivity.

He is here writing about mental infirmity, a touch of neurosis, but it’s interesting that he uses physical imagery: “forever offering its biceps to be felt, thumping its breast.” Is this thinking close to that which suggests that madness and creativity go often together, that we must be a little “cracked” to really understand life, and that if we see the world as it really is then we ought to be depressed?

His reference to the “Philistine type,” which sounds distinctly snobbish, made me think not only of the muscled, air brushed beauties that we see endlessly in magazines but also of the people we in medicine are trying to produce, working hard and using every strategy to achieve the harmony and perfection advocated by WHO. I fear that our whole enterprise is flawed by our failure to recognise that cracks, infirmities, failures, an acceptance of death and the fragility of everything are essential to health.

Soon after reading the passage by James I heard Leonard Cohen sing:

Ring the bells that still can ring

Forget your perfect offering

There is a crack in everything

That’s how the light gets in.

Without the crack we live in darkness.

And today I have read W B Yeats’s poem Crazy Jane Talks With the Bishop. It contains these lines:

‘Fair and foul are near of kin,

And fair needs foul,’ I cried.

And later:

‘For nothing can be sole or whole

That has not been rent.’

Earlier this month in Doha I heard a discussion on the “good death.” Humankind has never reached unanimity on the good life despite our best philosophical, literary, and theological brains working away at the problem for millennia. There will be no agreement on the “good life,” and similarly there can be no agreement on the “good death.”

“But can’t we at least agree on some minimum conditions?” said one panellist at the Doha meeting. “Isn’t it access to opiates, the possibility of a pain free death?”

“There can be no pain free death,” said a palliative care doctor in the audience. “We will suffer when we die. We are leaving everything, all those we love. It’s painful. It’s suffering. But out of that suffering, I have seen time and time again, can come joy, understanding, love, and learning.”

Our big mistake in medicine is to think of health and disease as opposites. They are not. They are intertwined like the double helix or the Aesculapian snakes.

Richard Smith was the editor of the BMJ until 2004 and is director of the United Health Group’s chronic disease initiative.