My father was a psychiatrist in the 1960s, ‘70s and ‘80s. Like many mental health practitioners of his time, he tended to define people by their supposed pathologies: “This one is a depressive,” or “That one is borderline,” and even “Oh, she’s got a paranoid personality.” The emphasis was on the individual's illness as if they caused it.

Thankfully, mental health awareness has progressed significantly since then. With anxiety and depression reaching epidemic levels, the movement to understand a...