Suffering from depression and getting the flu aren’t the same thing, but mental illness is, for the most part, treated a lot like physical illness. Both are understood through a binary framework that distinguishes between health and sickness, order and disorder, function and dysfunction. This framework — the medical model — treats mental illnesses like depression and schizophrenia as natural, uniform entities that, like physical illnesses, can be empirically discovered and described. Just as you can get the flu, you can get depressed.

The main purveyor of the medical model of mental illness is the Diagnostic Statistical Manual of Psychiatric Disorders, or the DSM, a compendium of psychiatric disorders first issued in 1952 that conceptualizes mental illnesses as “dysfunctions” that occur “inside the head” of the patient.

As anyone who has taken Intro to Psych knows, the DSM has been controversial from the start. Supporters argue that the medicalization of mental illness, as embodied by the DSM, is beneficial for those suffering from mental illness and their loved ones. It legitimates mental illness in the public discourse and undermines pervasive ideas that mental illness is not real or is exaggerated by patients — or that mental illness reflects a defect of moral character or a “weakness of will.”