Final answer:
Historically, mental illness was often attributed to supernatural causes before the recognition of medical and genetic factors. Figures like Georget and Esquirol shifted the perception to organic afflictions with observable symptoms. The DSM now provides standardized diagnostic criteria for mental illnesses.
Step-by-step explanation:
Early in human history, mental illness was commonly believed to be caused by supernatural forces, such as demonic possession or the wrath of the gods. This perspective was prevalent before the emergence of scientific and medical explanations for mental health conditions, which we now understand can result from life experiences, genetics, drug usage, or brain trauma. Notably, throughout history, there have been shifts in how mental illness is perceived and classified, as seen in the demedicalization of certain behaviors and conditions like drapetomania during the Civil War era and homosexuality until 1973. In modern times, the biochemical theory suggests that mental illnesses are linked with the level of neurotransmitters in the brain, influencing conditions such as depression, anxiety, and schizophrenia.
Georget and Esquirol were key figures in the early modern psychiatry movement in France, both proposing physical and observable symptoms as the basis for mental illness, turning away from moral or theological explanations. They stressed that mental illnesses are organic afflictions, similar to other diseases. Despite a historical reliance on mistaken beliefs, such as physiognomy, the field has steadily advanced toward a more scientific understanding with the development of the Diagnostic and Statistical Manual of Mental Disorders (DSM), which outlines the criteria for diagnosing various mental disorders.