[The idea of the "incubation" of madness and its significance in the development of French forensic psychiatry during the first third of the 19th century].

The aim of this study is to attempt to demostrate the way in which a concept created by French psychiatrists during the first decades of the 19th century, that of the "incubation de la folie", contributed to the recognition of alienists as the great experts in the phenomenon of madness. In the first instance, the author considered how the idea of the "incubation" of madness was formulated by these incipient specialists in mental medicine, and then went on to deal with how this new concept was used in the courts of law and how it was contested by those sectors opposed to the psychiatrists hope of being accepted by society as being the only people capable, with a high degree of certainty, of establishing a subject's mental state and, consequently the degree of responsibility with which they had acted when breaking the law. This led to the idea or "incubation" being inmmersed in a debate, sometimes as the protagonist, which surpassed the limits of the field or Medicine. The last part of the study will try to show that the development of this scientific concept was strongly conditioned at the beginning of its formulations prevalent in France at that time.