Bion and Winnicott have exerted a profound influence on the theory and practice of clinical psychoanalysis. This paper addresses the radical departure of late Bion's and Winnicott's clinical ideas and practices from traditional psychoanalytic work, to what the author regards as a major “scientific revolution” in clinical psychoanalysis - from “extension” to “paradigm shift,” to use Thomas Kuhn's (1962) terminology. Drawing on Khunian terminology, the profound significance and implications of their thinking for the foundations of clinical psychoanalysis and for the analytic process are explored. The focus is in particular on late Bion's conception of “transformation in O,” and Winnicott's clinical-technical revision of the analytic work, with its emphasis on regression in the treatment of more disturbed patients. The author underscores in both late Bion's and Winnicott's innovations, the radical ontological experience of patient-and-analyst being-in-oneness at a primordial point of origin, in order to reach and transform the patient's unknown and unknowable, unrepresented states, mainly of core catastrophe (Bion) and unthinkable breakdown and madness (Winnicott).

The author suggests that the major revolution that late Bion's and Winnicott's clinical thinking introduced be termed “quantum psychoanalysis,” and it may co-exist with classical psychoanalysis just as classical physics co-exists with quantum physics.