Depression

A persistent, often disabling mood disorder characterised by sustained low affect, anhedonia, fatigue, distorted negative cognition, and in severe cases suicidality. Clinically distinguished from ordinary sadness by duration, intensity, and functional impairment, but the boundaries are fuzzy — depression shades into grief, anxiety, and personality features like narcissism, and there is little consensus on its underlying causes. A recurring subject for David Foster Wallace, whose work — including Kate Gompert's chapters in Infinite Jest and the title character of "The Depressed Person" — treats it as both clinical condition and existential predicament.

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