Depression is not a concrete thing

Functional mental illness is an abstract not concrete concept. It differs from organic mental illness where there is brain dysfunction.

Illnesses tend to be seen as “things” which people “have” (see eg. previous post). Since the nineteenth century with the elucidation of pathological mechanisms, our positive understanding has become that the “thing” that people “have” is a diseased organ or bodily system. This model fits for organic mental illness such as dementia or delirium. For example, organic mental illness can be caused by a primary brain disorder or be secondary to a systemic illness. But functional mental illness, such as depression, is not primarily due to brain disease, although it can arise as a secondary consequence of illness. People are depressed, not their brains.

People of course are not separate from their bodies. They are alive, not machines, and embedded in their environment, which is social and cultural. Their bodies and environment afford various possibilities of action to them. Mechanistic dysfunctions of body parts may help to explain disease and why the person is ill. But the experience of illness is not necessarily due to diseased body parts. 

Depression, therefore, needs to be understood as a personal illness not a bodily disease caused by brain dysfunction. Its social implications can mean that various roles cannot be fulfilled, such as being able to go to work. It is not simply curable by willpower and motivation and, therefore, the person themselves should not be blamed for their illness. The expectation is that people will try to recover as quickly as possible with appropriate help and care if necessary. 

None of these social implications of illness necessarily require the presence of bodily disease to be entitled to the rights and obligations of the sick role (see eg. previous post). Such illness is not concrete in the sense of being caused by bodily mechanisms. But, functional mental illness, such as depression, even though abstract rather than concrete, is still real and valid. Regarding depression as a physical thing in the brain is a category error and does not make sense (see eg. previous post).