In his later 'drive' theory, on which psychoanalysis was based, he introduced the dualism of psycho-dynamic conflict between 'bad' instinct, or Id, and 'good' social conscience, or Superego. Jung was unambiguous about original sin, regarding it as 'emotional fact'. He believed evil to be a real archetypal presence within human nature, and famously rejected the theological doctrine of privatio boni which, contrary to the doctrine of original sin, held evil to exist only in the absence of good. For Jung, the task of therapy was an extension of the work the Christian church had always done, of hearing the confession of guilty secrets, and helping to 'make the crooked plant grow straight'. Patients must be convinced of the duality of their nature before they could be helped.
Dualism is also implicit in the work of humanistic pioneers.
But this of course is not the same as saying that there is no bad side. Rogers' well-known reluctance to consider child abuse as a possible cause of neurosis implied that neurosis must be endemic to human nature. 0000 Existential therapy too can be dualistic. Irvin Yalom, for example, in his account of the famous 'Love's Executioner' case, writes of neurosis as a diseased limb that the therapist must attempt to severe a bad part to be got rid of if the good is to flourish. Dualistic assumptions also underlie transpersonal approaches.