the term ‘crown prince’ had originated with Freud in a letter underlining his dismay that, just when he had invested Jung with such a status within the scientific kingdom of psychoanalysis, the latter had taken the occasion to emphasize a psychologically significant coincidence
Beebe identifies the precise historical origin of the ‘crown prince’ designation in Freud’s correspondence, framing it as a title whose implicit rational-scientific demands Jung was compelled to repudiate through his embrace of irrational modes of knowing.
, Energies and Patterns in Psychological Type: The Reservoir of Consciousness, 2017thesis