It is just twenty years ago that I read a paper on the “Problem of Psychogenesis in Mental Disease” before this Society. William McDougall, whose recent death we all deplore, was in the chair. What I then said about psychogenesis could be safely repeated to-day, for it has left no visible traces, or other noticeable consequences, either in text-books or in clinics. Although I hate to repeat myself, it is almost impossible to say something wholly new and different about a subject which has not changed its face in the many years that have gone by. My experience, however, has increased and some of my views have matured, but I could not say that my standpoint has had to undergo any radical change. I am therefore in the somewhat uncomfortable situation of one who, on the one hand, believes that he has a well-founded conviction, but, on the other hand, is afraid to indulge in the habit of repeating old stories. Although psychogenesis has been discussed long ago, it is still a modern, even an ultra-modern, problem.