The growing redness (rubedo) which now follows denotes an increase of warmth and light coming from the sun, consciousness. This corresponds to the increasing participation of consciousness, which now begins to react emotionally to the contents produced by the unconscious. At first the process of integration is a "fiery" conflict, but gradually it leads over to the "melting" or synthesis of the opposites. The alchemists termed this the rubedo, in which the marriage of the red man and the white woman, Sol and Luna, is consummated. Although the opposites flee from one another they nevertheless strive for balance, since a state of conflict is too inimical to life to be endured indefinitely. They do this by wearing each other out: the one eats the other, like the two dragons or the other ravenous beasts of alchemical symbolism.
— Carl Gustav Jung
Consciousness arriving as heat — not clarity, not calm understanding, but something that burns. The rubedo refuses the cooler register of insight; it names something closer to what actually happens when the psyche begins to integrate what it has been avoiding. Not a dawning recognition but a conflict, one in which the solar and the lunar, the formed and the fluid, tear at each other before anything resembling synthesis is possible.
The temptation is to read the later stages of this process — the *coniunctio*, the completed marriage — as the real point, and to treat the fiery conflict as regrettable transit. That is the pneumatic preference showing its hand: get through the suffering and arrive at the unity. But Jung is precise here. The opposites do not resolve because they reconcile; they resolve because they exhaust each other. One eats the other. What is left is not a higher harmony achieved by good will or spiritual discipline — it is what survives mutual consumption. The alchemists kept the devouring beasts in the image because removing them would have falsified it.
Warmth and light come from the sun, yes — but they come into a process that is already consuming itself. Integration here is not addition. It is what remains after enough has been destroyed.
Carl Gustav Jung·Mysterium Coniunctionis: An Inquiry into the Separation and Synthesis of Psychic Opposites in Alchemy·1955