In Modern Man in Search of a Soul, Carl Jung examines how artists freely channel unconscious forces into their art and how understanding art can help reveal the truth about the human psyche:
It is not alone the creator of this kind of art who is in touch with the night-side of life, but the seers, prophets, leaders and enlighteners also. However dark this nocturnal world may be, it is not wholly unfamiliar. Man has known of it from time immemorial—here, there, and everywhere; for primitive man today it is an unquestionable part of his picture of the cosmos. It is only we who have repudiated it because of our fear of superstition and metaphysics, and because we strive to construct a conscious world that is safe and manageable in that natural law holds in it the place of statute law in a commonwealth.
Yet, even in our midst, the poet now and then catches sight of the figures that people the night-world—the spirits, demons and gods. He knows that a purposiveness out-reaching human ends is the life-giving secret for man; he has a presentiment of incomprehensible happenings in the pleroma. In short, he sees something of that psychic world that strikes terror into the savage and the barbarian.
It is therefore to be expected of the poet that he will resort to mythology in order to give his experience its most fitting expression. It would be a serious mistake to suppose that he works with materials received at second-hand. The primordial experience is the source of his creativeness; it cannot be fathomed, and therefore requires mythological imagery to give it form. In itself it offers no words or images, for it is a vision seen “as in a glass, darkly.”
It is merely a deep presentiment that strives to find expression. It is like a whirlwind that seizes everything within reach and, by carrying it aloft, assumes a visible shape. Since the particular expression can never exhaust the possibilities of the vision, but falls far short of it in richness of content, the poet must have at his disposal a huge store of materials if he is to communicate even a few of his intimations. What is more, he must resort to an imagery that is difficult to handle and full of contradictions in order to express the weird paradoxicality of his vision.