[10] He left his job in 1884 and spent one year on medical study trips with Jean-Martin Charcot, a French neurologist in Paris, Bernhard von Gudden, a German psychiatrist in Munich, and to London.

[10] After these trips, he returned to Zürich to briefly work as assistant to Auguste Forel while completing his psychiatric residency at the Burghölzli, a university hospital.

Influenced by Bleuler, Carl Jung and Franz Riklin used word association tests to integrate Freud's theory of repression with empirical psychological findings.

Like Kraepelin, Bleuler argued that dementia praecox, or "the schizophrenias", was a physical disease process characterized by exacerbations and remissions.

In 1911, Bleuler wrote, "When the disease process flares up, it is more correct, in my view, to talk in terms of deteriorating attacks, rather than its recurrence.

[full citation needed] Bleuler agreed with Rudin that having a family member with schizophrenia increases an individual's chance of also having the disease.

[26] He followed Freud's perspective of seeing sexuality as a potent influence upon anxiety,[27] pondered on the origins of the sense of guilt, and studied the process of what he defined as switching (the affective shift from love to hate, for example).

He defined the psychoid as the capacity to respond and adapt to stimuli, creating permanent changes in the brain and shaping future reactions.

Under his direction at the Burghölzli clinic in Zurich, expert reports were produced supporting surgical interventions on eugenic grounds.

Bleuler's advocacy for eugenic sterilization significantly contributed to the widespread adoption of these practices in psychiatric institutions, most notably at the Burghölzli Clinic.

[32] Despite being a physician dedicated to healing, Bleuler conceptualized schizophrenia as a chronic and incurable illness, creating a contradiction at the core of his medical philosophy.

This paradox is particularly striking given that Bleuler expanded on Emil Kraepelin’s concept of dementia praecox while rejecting its strictly degenerative prognosis.

This perspective played a significant role in the medicalization of psychiatric conditions, contributing to a framework that justified eugenic interventions—such as sterilization—rather than treatments focused on recovery.

By framing schizophrenia as an irreversible condition, Bleuler reinforced a medical model that prioritized control and segregation over healing and reintegration.

This term reflected his belief that illnesses should not be treated with immediate, active intervention but rather by allowing their natural course to unfold, observing passively their decline, with the hope that recovery could occur.

Discharge required suppressing and controlling disruptive secondary symptoms, a process Bleuler and his successors referred to as "socialization".

By defining schizophrenia as a fixed biological defect rather than a dynamic condition with potential for improvement, Bleuler helped shape psychiatric practices with severe consequences for patients: • Involuntary commitment and Institutionalization – His theories justified the long-term confinement of individuals with schizophrenia in asylums rather than efforts to reintegrate them into society.

His approach aligned more with eugenics and social control than with the Hippocratic ideal of healing, making his legacy philosophically and ethically questionable to this day.

In the editions published in Germany in 1937 and 1943, Manfred Bleuler included articles by racial hygienists such as Hans Luxenburger and Friedrich Meggendorfer.

In postwar editions of the widely respected textbook, these additions were removed and replaced with questionable references to psychiatric methods such as lobotomy (brain surgery) and neuroleptics (psychotropic medication).

The introduction of lobotomy and neuroleptics after the war, while possibly aiming to reflect a shift in psychiatric treatments, also have contributed to harmful practices.

Lobotomies, as well as Neuroleptics were deeply controversial despite their widespread use, and would later become subjects of ethical scrutiny due to concerns over their overuse, side effects, and questionable application in treating vulnerable patients.