psychology that treats the psyche as an epiphenomenon would better call itself brain-psychology… there are no grounds at all for regarding it as a mere epiphenomenon, dependent though it may be on the functioning of the brain.
Jung’s foundational argument that the psyche possesses irreducible ontological status and cannot be legitimately classified as a secondary by-product of cerebral processes.
, The Structure and Dynamics of the Psyche, 1960thesis