This article elaborates a claim, first introduced by Wilhelm Dilthey, that metaphysics represents an illusory flight from the tragedy of human finitude. Metaphysics, of which psychoanalytic metapsychologies are a form, transforms the unbearable fragility and transience of all things human into an enduring, permanent, changeless reality, an illusory world of eternal truths. Three “clinical cases” illustrate this thesis in the work and lives of a philosopher and two psychoanalytic theorists: Friedrich Nietzsche and his metaphysical doctrine of the eternal return of the same, Sigmund Freud and his dual instinct theory, and Heinz Kohut and his theoretical language of the self. It is contended that the best safeguard against the pitfalls of metaphysical illusion lies in a shared commitment to reflection on the constitutive contexts of all our theoretical ideas.