Right at the beginning you meet the "dragon," the chthonic spirit, the "devil" or, as the alchemists called it, the "blackness,'' the nigredo, and this encounter produces suffering.... In the language of the alchemists, matter suffers until the nigredo disappears, when the "dawn" (aurora) will be announced by the "peacock's tail'' (cauda pavonis) and a new day will break, the leukosis or albedo. But in this state of "whiteness" one does not live in the true sense of the word, it is a sort of abstract, ideal state. In order to make it come alive it must have "blood," it must have what the alchemists call the rubedo, the "redness" of life. Only the total experience of being can transform this ideal state of the albedo into a fully human mode of existence. Blood alone can reanimate a glorious state of consciousness in which the last trace of blackness is dissolved, in which the devil no longer has an autonomous existence but rejoins the profound unity of the psyche. Then the opus magnum is finished: the human soul is completely integrated.
— Edward F. Edinger
Edinger is quoting Jung directly here, and the passage deserves to be read against its own triumphalism. The sequence it describes — nigredo, albedo, rubedo — is a genuine map of something the psyche moves through. But the endpoint Edinger names, the soul "completely integrated," the devil dissolved, the opus finished, is the place to pause. It has the grammar of a redemption arc, and that grammar lies.
The albedo is real. There are states where the blackness recedes, where something clarifies, where the suffering that characterized the descent goes quiet. And the passage is right that this is not yet life — it is an abstract brightness, almost posthumous, a consciousness that has cleaned itself of something vital. What the rubedo names is the return of blood, of appetite, of the very mess the nigredo seemed to promise you were done with. The redness is not triumph; it is the soul finding out that integration is not the elimination of the difficult contents but their continued pressure inside a more spacious container.
What the alchemical language cannot quite say — though it keeps circling it — is that the opus never finishes. The "last trace of blackness" dissolved is a fantasy drawn from the desire not to suffer, dressed in gold. The rubedo's gift is not completion. It is that the suffering no longer runs the operation from below, hidden, but meets you face to face.
Edward F. Edinger·The Mysterium Lectures: A Journey Through C.G. Jung's Mysterium Coniunctionis·1995