Hans Eysenck

The continued hostility of Freudians to all forms of criticism, however well-informed, and to the formulation and existence of alternative theories, however well-supported, does not speak well for the scientific spirit of Freud and his followers. For any judgement of psychoanalysis as a scientific discipline, these points must constitute strong evidence against its acceptance.

Hans Eysenck, Decline and Fall of the Freudian Empire, New York, 1985, pp. 13-14