The Archetypes and The Collective Unconscious (Collected Works of C.G. Jung Vol.9 Part 1)

Although common prejudice still believes that the sole essential basis of our knowledge is given exclusively from outside, and that “nihil est in intellectu quod non antea fuerit in sensu,” it nevertheless remains true that the thoroughly respectable atomic theory of Leucippus and Democritus was not based on any observations of atomic fission but on a “mythological” conception of smallest particles, which, as the smallest animated parts, the soul-atoms, are known even to the still Paleolithic inhabitants of central Australia.

How much “soul” is projected into the unknown in the world of external appearances is, of course, familiar to anyone acquainted with the natural science and natural philosophy of the ancients.

It is, in fact, so much that we are absolutely incapable of saying how the world is constituted in itself—and always shall be, since we are obliged to convert physical events into psychic processes as soon aswe want to say anything about knowledge.

But who can guarantee that this conversion produces anything like an adequate “objective” picture of the world? ~Carl Jung, CW 9i, Para 116.