Forty years ago, David Rosenhan, a professor at Stanford University, conducted one of the most celebrated – or, as some still prefer, notorious – experiments in medical history.

Rosenhan saw psychiatry as risible mumbo-jumbo, based not on objective study of human behaviour but on undefinable, spaced-out assumptions. He set up what became known as the “Rosenhan Experiment”.
Three woman and five men presented themselves at separate mental hospitals across the US. None had ever been diagnosed with a psychiatric problem. Each told the duty psychiatrist that they were hearing voices saying three words: “Thud”, “Empty” and “Hollow”. Otherwise, they behaved as they ordinarily would. All were immediately admitted as patients.
None was released until she or he had accepted that they had been suffering from either schizophrenia or manic depression – on what basis they were allocated to one or other of the conditions is not known – and had agreed to take a course of powerful anti-psychotic drugs. Seven were detained for an average of 19 days, the eighth for two months.
Rosenhan published his results in the journal Science in March 1973. Immediately, leading US psychiatrists screeched “foul!”, suggesting that he must have coached his team to show accurate symptoms of mental illness. In this view, the hospitals hadn’t been exposed for bad practice but had merely been hoodwinked by a fraudster masquerding as a scientist.
One hospital challenged Rosenhan to send another bunch of “pseudopatients”, guaranteeing that this time they’d swiftly be rumbled. Over the following month, 193 new patients were admitted to the facility. Staff identified 41 as likely suspects, 19 as definite fakes. In fact, Rosenhan hadn’t sent anyone to the hospital.
Rosenhan wrote in Science that, “It is clear that we cannot distinguish the sane from the insane in psychiatric hospitals.”
The reputation of psychiatry was damaged, but not destroyed. To the extent that belief in the practice is irrational, it cannot be dented by research results or logical argument. And, anyway, who’s to tell a patient who’s feeling better after treatment that the treatment has been worthless? Moreover, psychiatry continues to be blessed by the fact that its best-organised and most vociferous opponents are the Scientologists, themselves widely regarded as unhinged. One US psychiatrist noted cheerfully that, “To be described as a charlatan by the Scientologists is almost an endorsement.”

The Rosenhan Experiment had the ironic effect of boosting the credibility of a rival school of psychiatry – or, perhaps, an alternative form of quackery. The bible of this tendency is the regularly updated “The Diagnostic and Statistical Manual of Mental Disorders” (DSM), which purports to classify all diseases and disorders of the mind. The DSM has pioneered the discovery of many new mental illnesses.
The journal is published by the American Psychiatric Association (APA), the representative body of US psychiatrists. It is the only publication of its kind and is routinely used by the Department of Health, hospitals, insurance companies and so on as a guide to the varieties of mental disorder.
The DSM famously defined homosexuality as a mental illness and only abandoned the designation in 1973 – not because it recognised that there was no scientific basis for it, but as a result of the rise of the gay liberation movement, which protested outside APA gatherings. The emergence of militant gay psychiatrists had a significant effect, too.
What the gay issue revealed was that the identification and categorisation of mental illnesses is as much a matter of politics and tradition as of objective diagnoses. In the extreme, wise women were once seen as mad harpies. Runaway slaves were thought to be of unsound mind.
‘Drapeomania’ was discovered by a doctor called Samuel Cartwright in Louisiana in 1850. It affected only slaves. An early symptom was unhappiness at being a slave. The effect of the full-blown illness was to make slaves run away.
It may seem obvious now that drapeomania was not a medical concept at all but a crude mechanism for pathologising behaviour which undermined the interests of a class in society dependent for its position on acceptance of slavery as a normal practice.
Likewise, for diagnosing women with spirit as deranged or proclaiming homosexual orientation an illness: heterodoxies which challenged prevailing assumptions had to be stamped out. The alternative to ducking supposedly stricken individuals into ponds
or subjecting them to electrotherapy lay in overthrowing the existing order. As far as the ruling class was concerned, that was totally intolerable.
Something similar happens today, if more subtly. The DSM’s confirmation of a new illness opens new markets for pharmaceutical companies. It was the DSM which first noted and named Antisocial Personality Disorder (APD). Luckily, Pfizer had a pill for it on the market in no time at all.
Again, medical practice is dictated by the interests of the powerful, rather than by the health of patients.
So dominant has this approach become that a faction of transgendered people in the US now argues that the condition is a form of illness after all, because that’s the only way they have any hope of persuading insurance companies to cover the procedures they need.
The result of it all is that great numbers of people in real need of mental health services are deprived of resources even as billions are spent marketing remedies to others who are actually well, but are worried about life – which in my own experience means almost all of us.