This literary essay examines and rehearses the conceptual challenge fatigue poses to diagnosis in its clinical and critical registers. Taking as its case study Joan Copjec’s essay “Battle Fatigue: Kiarostami and Capitalism”—wherein fatigue, conceptually declined from Levinas’ weariness of existence and the psychoanalytic death drive, is deployed as a theoretical lens through which to read Abbas Kiarostami’s film Taste of Cherry—this essay argues that Copjec’s diagnosis of Badii’s unexplainable suicidality qua fatigue mirrors the clinic’s insofar as both render fatigue into a diagnosis of exclusion predicated on forensic registers of negative evidence. For Copjec, fatigue is a symptom of Badii’s unexplainable suicidality, not its cause—a logic that effectively reproduces the clinic’s diagnosis of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) as the consequence of a suffering without proof. This results in Badii’s erasure as a clinical subject of weariness at the behest of a socio-historico-political metaconcept of fatigue. Acknowledging that this trade-off constitutes the dialectical challenge of theorizing any illness, this essay nevertheless argues that fatigue presents a unique theoretical dilemma, insofar as historically and into the present, warring ideological factions have harmoniously eschewed patho-clinical frameworks for a conceptualization of fatigue as the essential condition of life under capitalist modernity. When fatigue is a symptom of everything—of mere living—it becomes a symptom of nothing: it loses its clinical and critical valence. Copjec’s diagnosis, then, is not so much deficient as it is demonstrative: like Kiarostami’s film(s), it begins with a lack of evidence only to end at an aporetic standstill: the impossibility of shoring up the evidence of lack. Like the slash that separates “ME” from “CFS,” this essay argues that fatigue is not what slips through the crack between pre-existing categories of psyche and soma, but the very cut out of which these categories emerge, and upon whose negativity their fraught relation relies.