Across the depth-psychology corpus, ‘calm’ functions not as a simple absence of disturbance but as a positive, achieved state with distinct neurophysiological, psychological, and contemplative dimensions. The literature fractures into at least three major registers. In the somatic-trauma tradition—represented by Rothschild, Porges, Levine, and Ogden—calm is a precisely located autonomic condition, the parasympathetic ventral-vagal state that enables social engagement, clear cognition, and healing; its attainment is a clinical goal measurable by breath depth, heart-rate variability, and postural indicators, and its absence in traumatized individuals constitutes a diagnostic marker. In the contemplative and yogic streams—Aurobindo, Brazier, Nhat Hanh, the Upanishadic commentators—calm is an interior achievement that presupposes sustained meditative work; it is distinguished from mere passivity or emotional suppression and identified with the Sanskrit shanti or the Zen samadhi-quality of the therapist whose settled presence stabilizes the client. A third register, rooted in classical philosophy, locates calm as Aristotle’s praotes—the opposite of anger, a settled disposition toward equanimity—and in Hellenistic psychic galene, the sea-calm of the undisturbed soul. Tensions pervade the corpus: ACT explicitly decouples acting calmly from feeling calm; DBT treats calm as a product of behavioral technique rather than contemplative depth; Barrett reads calm as a socially constructed concept taught to children through shared conceptual frameworks. The term therefore names both a neurobiological target state and a philosophical ideal, and the corpus is richest precisely at their intersection.