Collected Works of C.G. Jung, Volume 11: Psychology and Religion: West and East
I have often been asked where the archetype comes from and whether it is acquired or not. This question cannot be answered directly.
Archetypes are, by definition, factors and motifs that arrange the psychic elements into certain images, characterized as archetypal, but in such a way that they can be recognized only from the effects they produce.
They exist preconsciously, and presumably they form the structural dominants of the psyche in general.
They may be compared to the invisible presence of the crystal lattice in a saturated solution.
As a priori conditioning factors they represent a special, psychological instance of the biological “pattern of behavior,” which gives all living organisms their specific qualities. Just as the manifestations of this biological ground plan may change in the course of development, so also can those of the archetype.
Empirically considered, however, the archetype did not ever come into existence as a phenomenon of organic life, but entered into the picture with life itself. ~”A Psychological Approach to the Dogma of the Trinity” (1942). In CW 11: Psychology and Religion: West and East. P. 222