How Schizophrenia Got Its Name — General Paresis, Kraepelin's Dementia Praecox and Bleuler, 1822–1913

This is the second part of a series on the history of psychiatry. Part 1 followed a period in which the treatment of mental illness was settled while its causes stayed unknown. This part is about the causes. Nineteenth-century asylums held one disease whose cause was eventually tracked down: general paresis. But the same approach did not carry over to the other patients. So the German psychiatrist Emil Kraepelin sorted diseases not by cause but by how they ran and how they ended. The name schizophrenia came out of that sorting.

This series is a history of psychiatry. It is not advice on diagnosis or treatment. If you are struggling with your mental or physical health, please talk to a doctor or a support service. The text includes names of illnesses and expressions that are no longer in use; they are given as they appear in the sources of the time.

A disease that killed within a few years

General paresis, also called general paralysis of the insane, was a disease in which mental and bodily symptoms advanced together. Memory failed, and delusions appeared, often of great wealth or power. Speech became slurred, the hands trembled, and convulsions set in. Most patients died within a few years. A paper of 1913 gives the average duration, as estimated by various authors, as 24 to 32 months.

It was not rare. Figures compiled in 1901 by R. S. Stewart, a physician at the Glamorgan County Asylum, show general paralytics making up about 8 percent of admissions to the asylums of England and Wales. Taken as five-year averages, the share was 8.7 percent for 1889–93 and 7.8 percent for 1893–97.

1822: Bayle calls it one disease

The man who marked it out as a single disease was a young French physician, Antoine Bayle. On 21 November 1822 he presented his doctoral thesis to the Faculty of Medicine in Paris.

For seventeen years French physicians had been describing these cases as "insanity complicated with paralysis" — a mental illness to which paralysis had been added. Bayle argued otherwise. When a general, incomplete paralysis and a disorder of the mind develop side by side, he said, they are symptoms of one and the same disease. And in the brains of patients who had died, he found signs of long-standing inflammation in the membranes that wrap the brain.

Writing in 1923, the Edinburgh psychiatrist George Robertson called this "an opinion never expressed before by anyone," one that had since been proved true in its essential features. Gather mental symptoms into one disease, then find the evidence for it in the brain: this is where that pattern was first shown.

Bayle got as far as the changes in the membranes. What produced them, he did not know.

Half a century of argument over syphilis

Many patients with general paresis had earlier had syphilis, an infection spread mainly by sex. Attention was first drawn to this in 1857.

Even so, the idea that syphilis was the cause was slow to win. There were two obstacles. One was time: many years passed between the infection and the paresis. The other was treatment: the remedies of the day worked on other signs of syphilis but did nothing for paresis. So paresis came to be seen not as syphilis itself but as a separate disease that followed it. The term in use was "metasyphilis."

An experiment was reported in 1897. At the International Medical Congress in Moscow, the Viennese psychiatrist Richard von Krafft-Ebing spoke on general paresis and mentioned it. According to an editorial in a British journal the following year, an unnamed specialist in Vienna had deliberately inoculated nine paretic patients with syphilis. The reasoning was that someone who has had the disease cannot catch it again. The editorial reports that six of the nine stayed free of syphilis and three contracted it. It then condemned any such experiment on asylum patients as "cowardly, immoral and infamous."

In 1905 the organism that causes syphilis was found, and in 1906 August Wassermann and his colleagues in Germany published a blood test for the disease. The test was soon applied to the spinal fluid of paretic patients, the fluid that bathes the brain and spinal cord. The link with syphilis grew stronger.

Opinion was still divided. Kraepelin, author of the leading German textbook of psychiatry, declared in 1904 that syphilitic infection was essential for the later appearance of paresis. Max Nonne, a German physician with enormous experience of syphilis and the nervous system, wrote in 1902 that paresis was not a syphilitic disease of the brain. What was missing was the decisive piece. Nobody had seen the organism itself inside a patient's brain.

1913: Noguchi examines seventy brains

The decisive piece came from Hideyo Noguchi, a Japanese bacteriologist at the Rockefeller Institute for Medical Research in New York. He worked with J. W. Moore, a physician at Central Islip State Hospital, whose pathology service held the brains of seventy patients who had died of general paresis.

Noguchi modified a method that stains the organism black with silver, and searched the tissue. The brain is packed with fine, winding fibres. The syphilis organism is itself a thin spiral, easy to lose among them. Their paper was received on 11 January 1913 and published in February.

The result: the organism was found in twelve of the seventy brains, from ten men and two women. It lay in every layer of the cortex, the grey outer sheet of the brain, except the outermost. It was not in the membranes, and not in the sheaths around the blood vessels. It had made its way into the nerve tissue itself.

The paper quotes a striking remark of Kraepelin's. The failure to find the organism, he had written, did not mean it was never there; it might have settled in places where no one had yet looked, or where it was hard to find. That is exactly where Noguchi found it.

The limits are plain as well. Twelve in seventy is about one in six; in the other fifty-eight brains nothing was found. Noguchi and Moore ended by saying that further work would decide whether better technique could show the organism in a much higher share of cases. And knowing the cause did not at once change the treatment. The treatment of paresis belongs to Part 4.

Kraepelin's classification: when the cause is unknown, sort by the course

General paresis became the first major case in which the cause of a mental illness was found in the body. But the approach did not work for the many other patients in the asylums. Nothing that could be called a cause had been found for them.

Emil Kraepelin (1856–1926) took another road. He is the same Kraepelin quoted above on syphilis: professor at Heidelberg, and the author of a textbook of psychiatry that he rewrote edition after edition.

Earlier classifications went by the most prominent symptom. An excited patient had mania; a dejected one had melancholia. But the same patient might be excited one month and dejected the next. Sorted by symptom, one person kept moving from disease to disease.

In the preface to his fifth edition, in 1896, Kraepelin announced a change of method. He would look not at the symptoms of the moment but at how an illness began, how it ran and how it ended. To do that he recorded his patients in detail and followed them after they left.

The scheme took its settled form in the sixth edition of 1899. Its preface says that the chapters on dementia praecox and manic-depressive insanity had been for the most part newly written.

Dementia praecox means, roughly, an early loss of mental powers: an illness that starts young and wears the mind down. As the American psychiatrist Kenneth Kendler showed in a 2020 study of the textbooks, Kraepelin brought together three conditions that had been described separately. One was marked by silly, disorganised behaviour (the hebephrenic form), one by frozen postures or wild excitement (the catatonic form), and one by delusions (the paranoid form). The first two had been described earlier by the German physicians Ewald Hecker and Karl Kahlbaum. The three look nothing alike. Kraepelin joined them because he saw shared underlying symptoms and a shared course.

Manic-depressive insanity, by contrast, was an illness of recurring excitement and depression with a return to normal in between. In this way the severe mental illnesses of unknown cause were divided in two, by their course.

Kraepelin knew the division was provisional. According to a 2011 study by Kendler and Assen Jablensky, he hoped for a "natural" classification but realised that the knowledge of causes it required would not be available in his lifetime. He sorted by course first, without waiting for causes. It is the same move as at the York Retreat in Part 1, where treatment was settled without knowing the cause.

Bleuler and the word "schizophrenia"

The name dementia praecox soon drew an objection. It came from Eugen Bleuler (1857–1939), director of the Burghölzli hospital in Zurich.

On 24 April 1908 Bleuler spoke at a meeting of the German Psychiatric Association in Berlin. In Kraepelin's dementia praecox, he said, it is "neither a question of an essential dementia nor of a necessary precociousness." Besides, no adjective or noun could be formed from the expression. He would therefore take the liberty of using the word schizophrenia.

He built it from the Greek for "to split" and "mind." What Bleuler had in view was the breaking apart of mental functions such as thought and feeling, which he took to be the most important sign of the illness.

In 1911 he published Dementia Praecox, or the Group of Schizophrenias. As the title says, he saw not one disease but a group. Nor did he think it was always incurable.

Kraepelin did not cling to his name either. In the eighth edition of his textbook he acknowledged that it was disputed and mentioned Bleuler's term. He described the illness as a series of states whose common characteristic is "a peculiar destruction of the internal connections of the psychic personality."

The name changed. The foundation did not: an illness of unknown cause, gathered together by its symptoms and its course.

What had been done, and what had not

First, what had been done. For general paresis it was shown that the mental and bodily symptoms belong to one disease (1822), and that its cause is the organism of syphilis (1913). In one disease, at least, the cause of a mental illness had been found in the body. For illnesses of unknown cause, a method was created: follow the course and sort by it. The distinction between dementia praecox and manic-depressive insanity survives, in altered form, in the diagnostic categories used today.

What had not been done is just as clear. The approach that worked for paresis did not spread to other illnesses. Neither Kraepelin nor Bleuler knew the cause of dementia praecox, and renaming it schizophrenia did not change that. The two also disagreed on whether it was one disease or several. And paresis itself, its cause now known, still could not be cured.

The grouping was settled before any cause was found. That left open how to understand mental illnesses that could not be explained from a cause. The next part turns to a contemporary who gave a completely different answer: Sigmund Freud, and psychoanalysis.