“All that is outside, also is inside,” we could say with Goethe.
But this “inside,” which modern rationalism is so eager to derive from “outside,” has an a priori structure of its own that antedates all conscious experience.
It is quite impossible to conceive how “experience” in the widest sense, or, for that matter, anything psychic, could originate exclusively in the outside world.
The psyche is part of the inmost mystery of life, and it has its own peculiar structure and form like every other organism.
Whether this psychic structure and its elements, the archetypes, ever “originated” at all is a metaphysical question and therefore unanswerable.
The structure is something given, the precondition that is found to be present in every case.
And this is the mother, the matrix—the form into which all experience is poured. ~Carl Jung, CW 9i, Pages 101-102