An 1809 description of a case that Pinel recorded in the second edition of his textbook on insanity is regarded by some as the earliest evidence for the existence of the form of mental disorder later known as dementia praecox or schizophrenia, although Emil Kraepelin is generally accredited with its first conceptualisation.

He spent fifteen years earning his living as a writer, translator, and editor because the restrictive regulations of the old regime prevented him from practicing medicine in Paris.

In the second competition, the jury stressed his ‘painful’ mediocrity in all areas of medical knowledge, an assessment seemingly so grossly incompatible with his later intellectual accomplishments that political motives have been suggested.

The Salpêtrière was, at the time, like a large village, with seven thousand elderly indigent and ailing women, an entrenched bureaucracy, a teeming market and huge infirmaries.

In it Pinel makes the case for the careful psychological study of individuals over time, points out that insanity isn't always continuous, and calls for more humanitarian asylum practices.

[5] In 1798 Pinel published an authoritative classification of diseases in his Nosographie philosophique ou méthode de l'analyse appliquée à la médecine.

The symptoms are described as “taciturnity, a thoughtful pensive air, gloomy suspicions, and a love of solitude.” [6]: 136  It is noted that Tiberius and Louis XI were subjected to this temperament.

[6]: 150–151  An instance where this type of species of mental derangement occurs where a mechanic, who was confined at the Asylum de Bicetre, experienced violent outbursts of maniacal fury.

Dementia is usually accompanied by raging and rebellious movement, by a quick succession of ideas formed in the mind, and by passionate feelings that are felt and forgotten without attributing it to objects.

[6]: 163  The specific character of dementia contains a rapid progression or continual succession of isolated ideas, forgetfulness of previous condition, repetitive acts of exaggeration, decreased responsiveness to external influence, and complete lack of judgment.

[6]: 164 The fifth and last mental derangement is called idiotism, or otherwise known as “obliteration of the intellectual faculties and affections.”[6]: 165  This disorder is derived from a variety of causes, such as extravagant and debilitating delight, alcohol abuse, deep sorrow, diligent study, aggressive blows to the head, tumors in the brain, and loss of consciousness due to blockage in vein or artery.

Many of the young people that have remained in the state of idiotism for several months or years are attacked by a spasm of active mania between twenty and thirty days.

[6]: 168  The specific character of idiotism includes partial or complete extermination of the intellect and affections, apathy, disconnected, inarticulate sounds or impairment of speech, and nonsensical outbursts of passion.

[6]: 172 In his book Traité médico-philosophique sur l'aliénation mentale; ou la manie, published in 1801,[10] Pinel discusses his psychologically oriented approach.

[12][13] Pinel noted, for example, that: "being held in esteem, having honor, dignity, wealth, fame, which though they may be factitious, always distressing and rarely fully satisfied, often give way to the overturning of reason".

Pinel argued that psychological intervention must be tailored to each individual rather than be based solely on the diagnostic category, and that it must be grounded in an understanding of the person's own perspective and history.

He insisted that psychological techniques should always be tried first, for example "even where a violent and destructive maniac could be calmed by a single dose of an antispasmodic [he referred to opium], observation teaches that in a great number of cases, one can obtain a sure and permanent cure by the sole method of expectation, leaving the insane man to his tumultuous excitement... ...and [furthermore] seeing, again and again, the unexpected resources of nature left to itself or wisely guided, has rendered me more and more cautious with regard to the use of medications, which I no longer employ—except when the insufficiencies of psychological means have been proven."

He believed in "the art of subjugating and taming the insane" and the effectiveness of "a type of apparatus of fear, of firm and consistent opposition to their dominating and stubbornly held ideas", but that it must be proportional and motivated only by a desire to keep order and to bring people back to themselves.

Based on his observations, he believed that those who were considered most dangerous and carried away by their ideas had often been made so by the blows and bad treatment they had received, and that it could be ameliorated by providing space, kindness, consolation, hope, and humor.

He recommended that recovered patients be employed, arguing that "They are the ones who are most likely to refrain from all inhumane treatment, who will not strike even in retaliation, who can stand up to pleading, menaces, repetitive complaining, etc.

Pinel also emphasized the necessity for leadership that was "thoughtful, philanthropic, courageous, physically imposing, and inventive in the development of maneuvers or tactics to distract, mollify, and impress" and "devoted to the concept of order without violence", so that patients are "led most often with kindness, but always with an inflexible firmness."

"[15] Pinel is generally seen as the physician who more than any other transformed the concept of 'the mad' into that of patients needing care and understanding, establishing a field that would eventually be called psychiatry.

milieu) therapeutic approaches; history-taking; nosography (the science of the description of syndromes); broadly-numerical assessments of courses of illness and treatment responses;[4] and a record of clinical teaching.

For example, Vincenzo Chiarugi, in the 1780s in Italy, removed metal chains from patients but did not enjoy the same renown bestowed on the more explicitly humanitarian Pinel who was so visible from late 18th century revolutionary France.

[12] In France, Joseph D'Aquin in Chambéry permitted patients to move about freely and published a book in 1791 urging humanitarian reforms, dedicating the second edition in 1804 to Pinel.

[citation needed] Pinel's most important contribution may have been the observation and conviction that there could be sanity and rationality even in cases that seemed on the surface impossible to understand, and that this could appear for periods in response to surrounding events (and not just because of such things as the phase of the moon, a still common assumption and the origin of the term lunatic).

By the mid-19th century in England, the Alleged Lunatics' Friend Society was proclaiming the moral treatment approach was achieved "by mildness and coaxing, and by solitary confinement", treating people like children without rights to make their own decisions.

Foucault also suggested that a focus on the rights of patients at Bicetre was partly due to revolutionary concerns that it housed and chained victims of arbitrary or political power, or alternatively that it might be enabling refuge for anti-revolutionary suspects, as well as just 'the mad'.

[19] Scull argues that the "...manipulations and ambiguous 'kindness' of Tuke and Pinel..." may nevertheless have been preferable to the harsh coercion and physical "treatments" of previous generations, though he does recognise its "...less benevolent aspects and its latent potential ... for deterioration into a repressive form...."[20]: 81–82  Some[who?]

have criticised the process of deinstitutionalization that took place in the 20th century and called for a return to Pinel's approach, so as not to underestimate the needs that mentally ill people might have for protection and care.