Theory Determines What Psychiatry and Medicine Think and Do |
Theory is our basic scientific tool for establishing knowledge. It dictates how we conduct patient care, teaching, and research.1 Once adopted, it simply becomes automatic, those guided by it typically unaware of its power and often unable to articulate it. While familiar scientific methods, such as randomized controlled trials, define how we conduct studies, philosopher Karl Popper emphasizes that theory determines what research questions we will examine with these methods.2
Two theories that have guided psychiatry and medicine since the 5th century B.C., and a third one lies on the horizon.
From the origin of scientific medicine with Hippocrates in the 5th century B.C. until Descartes’s Mind-Body Split Theory in the 17th century A.D., the Four Humors Theory guided medicine, not completely extinguished from health care until the 20th century. This naturalistic theory replaced the previous supernatural understandings that Greek gods caused symptoms as punishment for varied transgressions. The theory posited that an imbalance of four circulating humors (black bile, yellow bile, blood, phlegm) created disease and caused symptoms and often disability and death. For example, an imbalance of black bile might lead to melancholia or depression, while an imbalance of phlegm could make one phlegmatic. And the gruesome treatment to restore an imbalance was bloodletting, sometimes exsanguinating the patient. Fortunately, physicians would gradually replace it.
Descartes’s mind-body split theory surfaced in the 17th century and would slowly replace the Four........