Bernard Gibello is a professor at the University of Paris-X-Nanterre and the director of the Laboratory for Cognitive-Intellectual Exploration, Child Psychology Clinic, at Pitié-Salpêtrière Hospital, Paris. He is the president of the French Psychiatric Association.

‘For a long time, madness was not regarded as an illness. Even nowadays, psychiatry occupies a separate place in medicine. In the 19th century the clinical method made it possible to describe most mental illnesses with great precision, but, in contrast to other illnesses, it was still impossible to trace a disorder’s aetiology, as in neurology.
‘Over the past 150 years, numerous forms of psychopathology have been proposed, but none is sufficiently general to fit all types of madness. Aetiological heterogeneity has led the World Health Organization and the American Psychiatric Association to reject all aetiopathological and psychopathological hypotheses, in the interests of an allegedly more objective behavioural approach.
‘Clinical experience and reflection show, on the contrary, that mental pathology cannot be understood from a single perspective but, rather, from a multitude of influences and discoveries, mainly dating from the 20th century. Each one of them has cast light on some of the mysteries of mad thought. In this book, I have tried to propose a synthesis of them all,’ writes Bernard Gibello.

• What forms thought and what explains its dysfunctions?
• Besides examining recent findings, Professor Bernard Gibello provides a review of more than two centuries of debates.