The thin line between insanity and creative genius

'What for one culture is a marker of madness is for another an unremarkable aspect of the mind's life'

Like most announcements and unveilings in the field of genetics, the news that a schizophrenia gene has been identified by scientists needs to be treated with some caution. Imagine a headline reading "Caster sugar identified as causing meringues", and you will have a passable model for how much is often left out in the attempt to compress scientific complexity into a newspaper headline.

Like most announcements and unveilings in the field of genetics, the news that a schizophrenia gene has been identified by scientists needs to be treated with some caution. Imagine a headline reading "Caster sugar identified as causing meringues", and you will have a passable model for how much is often left out in the attempt to compress scientific complexity into a newspaper headline.

Nevertheless, the identification by German researchers of a gene implicated in inherited schizophrenia is clearly another step towards a fuller understanding of a disease - another step towards the notional goal of cure or prevention.

A clear enough step, anyway, to alarm those for whom the notion of genetic control over human biology has a dark shadow and for whom the notion of "cure" is a decidedly ambiguous one. On Radio 4's Today programme yesterday, Gwynneth Hemmings, of the Schizophrenia Association, warned against simplistic notions that we could eradicate schizophrenia by antenatal screening, for instance. And later this month the biochemist David Horrobin, the association's president, will publish The Madness of Adam and Eve: how schizophrenia shaped humanity, a work that argues that the disease is intimately, even inseparably, linked to the development of human culture.

The same mutation that triggered the ascent of man, Horrobin suggests, is responsible for the descent of individual men and women into madness. The emergence of this particular twist of our DNA signalled the divergence "between our large-brained, possibly pleasant, but unimaginative ancestors and the restless, creative creatures that we are today".

At one level this is a programme of rehabilitation for an illness that has been crudely demonised in the past. It comes complete with the kind of celebrity recruitment programme familiar from other consciousness-raising exercises, from Parkinson's disease to homosexuality.

Schumann, Strindberg, Kafka and Wittgenstein all betrayed schizotypal tendencies, we are told, and offer evidence of the close kinship between mental instability and creativity. There is a persuasive logic at work here. The classic symptoms of some forms of schizophrenia - delusions, hallucinations and wild associations of thought - have their respectable counterparts in notions of artistic and creative ability. The thoughts of a schizophrenic may well be "loosely connected", as one description has it, but it is just such loose connections that allow new and important connections to be formed - whether they are poetic or scientific.

This is scarcely an unprecedented flash of genius in itself. Dryden expressed it first and most concisely in Absalom and Achitophel, concluding his allegorical portrait of the Earl of Shaftesbury with the celebrated couplet: "Great wits are sure to madness near allied/ And thin partitions do their bounds divide." Since then it has become almost a commonplace, cemented into position by Freud's further associations between creativity and neurosis.

But our attitude to schizophrenia and its symptoms might move further yet; in his recent book Malignant Sadness, Lewis Wolpert noted that "in West Africa even mild depression may be associated with the sort of hallucinations that are, in the West, usually associated with schizophrenia." In other words, what for one culture is a marker of clinical madness is, for another, a pretty unremarkable aspect of the life of the mind.

But why is it that natural selection has fixed schizophrenia in the genome? The argument that it is the flip-side of our distinctive ingenuity and invention is one solution. Another, proposed by the evolutionary psychiatrists Anthony Stevens and John Price, is that schizophrenic types were invaluable in early human society, when rapid growth of social groups necessitated regular splitting into smaller tribes.

The schizoid type, they suggest, is "enabled by his borderline psychotic thinking to separate himself from the dogma and ideals of the main group, and to persuade his followers that he is uniquely qualified to lead them to salvation in a promised land".

Dryden's identification of the kinship between genius and insanity was a prejudicial one, entirely satirical in its intentions. We have learnt since then to be far more open-minded about the differences between what we admire in the human mind and what we fear.

But the poet's image of "thin partitions" is still a useful one, particularly in the field of evolutionary biology, where the divisions between success and failure may be infinitesimally small. Even the most optimistic proponent of genetic medicine would probably admit that, for the moment anyway, the instruments we possess are still too blunt to use on such delicate structures. Should we try to cut out the disease with such crude tools, we may well find that we have cut out what first made us human, too.

sutcliff@globalnet.co.uk