Materialistic prejudice explains it as a mere epiphenomenal by-product of organic processes in the brain. Any psychic disturbance must therefore be an organic or physical disorder which is undiscoverable only because of the inadequacy of our present methods of diagnosis.
Jung identifies psychiatric materialism’s core axiom — that psychic disturbance is reducible to undetected organic disorder — as a prejudice rather than an established truth, challenging it on the grounds that psyche may be primary.
, Psychology and Religion: West and East, 1958thesis