This is a concept discussed by Nietzsche. As has been stated previously, he had an understanding of what would be considered wholeness. He knew to be the Total Man it required more than just “light.” All parts of the Self were necessary and there for a reason. He saw that half of this Self was denied by most. This other half or dark is the Dionysian aspect. The light side, Apollonian.
Let's take a look at the Two Greek Gods in question here to have a little better picture. Apollo was the Sun God. He represented all that would be considered right (controlled). That would include logic as well as harmony, progress, clarity, and the principle of individuation. Dionysos on the other hand is the opposite (passion). He represents disorder, intoxication, emotion, ecstasy and unity. The god of Wine. He broke social boundaries. Here we are starting to see the picture of Wotan. He is both of these in one and as we know not only our High God, but one to emulate.
We can see this combination or joining of the two across many traditions, but for now we'll relate controlled passion back to our own myths, concepts, and even runes. It is very obvious to see in relation to the Mead theft, but instead we'll look at Siegfried. As we may know, he is able to cross the “wavering flames” to Brünnhilde because he has no fear. Perhaps no fear can be viewed as one who is not afraid of his Dionysian aspect as most men are. They try to hide or suppress this part of themselves rather than use it, to join with it, as Siegfried does. The Valkyrie in many ways fits well here when we think of “passion.” Death, chaos, transformation but also beauty and ecstasy. He becomes more whole like the Hagal Rune itself.
On wholeness or the World Tree itself, we can think of Irminsul. In Runes, we have Ir, Man, and Sol. This is reminiscent of the name Irman as well. A great Hero also and he was quite complete. Nonetheless, when we think of the microcosm of the Tree (ourselves) we begin to see “controlled passion” here too. Ir being representative of the feminine/Dyonisian and Man being that of the masculine/Apollonian. Light and Dark joined to make a third being Sol. Once this takes place within, victory goes with him everywhere as the Rune song states. To add, we can also associate the alchemical process with Irminsul, black, white, and red. They all fit with the Runes in question and all of what has been presented so far is initiation in and of itself.
In summary, Nietzsche seemed to have an understanding just like other esoteric disciplines/traditions did on what led to a higher being. He understood that both were needed. To close, he also knew that this was not the end, just a new beginning. Just like Od and Menglad continue on together after their unification, so too does the Ubermensch. He or maybe better said “We” eternally becomes……..