archetypes are not determined as regards their content, but only as regards their form and then only to a very limited degree… The archetype in itself is empty and purely formal, nothing but a facultas praeformandi, a possibility of representation which is given a priori.
Jung’s canonical formulation of the archetype as a contentless formal potential — a pre-existing structuring capacity rather than an inherited image.
, The Archetypes and the Collective Unconscious, 1959thesis