Mortality Constraint names the condition by which finitude itself becomes a generative principle — not merely a biological fact but a structural requirement for the production of value, virtue, ethics, and psychological depth. Across the depth-psychology corpus, the term appears at the intersection of several major lines of inquiry. Nussbaum, drawing on Aristotle and Lucretius, argues most directly that the urgency of justice, moderation, and erotic love depends constitutively on mortality: remove death, and virtue becomes optional or pointless. Peterson extends this Nussbaumian insight into Jungian and Homeric terrain, contending that mortal constraint is precisely what divine omnipotence cannot replicate — it is the crushing weight of finitude that generates the capacity to create value, a capacity that drives even Yahweh toward incarnation. Frank identifies the cultural pathology of evading this constraint: the restitution narrative deconstructs mortality into replaceable bodily parts, foreclosing the existential recognition that one’s whole being is mortal. Yalom locates mortality’s psychological work in the confrontation with death anxiety, arguing that its repression produces the major forms of psychopathology, while authentic encounter with it catalyzes awakening. The ascetic literature surveyed by Sinkewicz frames the constraint differently: the voluntary memory of death is a practised discipline that reorders the monk’s relationship to time, possession, and the body. Taken together, these voices converge on the paradox that mortality is not what diminishes human life but what makes it irreducibly serious.