Early in 1979 I was invited to contribute to a special number of the Canadian Journal of Psychiatry to honour Emeritus Professor Eric Wittkower who had held a chair of psychiatry at McGill University in Montreal from 1952 to 1964 and was then celebrating his eightieth birthday. This I was very glad to do. The resulting paper, with the above title, also formed the basis of lectures that I gave on various occasions during subsequent years. On one such occasion, in Rome, I met with two cognitive therapists, Giovanni Liotti and Vittorio Guidano, and was surprised and delighted to find how much we had in common. One consequence of our meeting was an invitation to contribute to a volume on Cognition and Psychotherapy being edited by Michael Mahoney and Arthur Freeman. This provided an opportunity to expand the original brief paper and led to the version that follows.