An instance of fruitful cross-disciplinary contacts is examined in detail. The ideas involved include (1) the double-blind hypothesis for schizophrenia, (2) the critique of game theory from the viewpoint of anthropology and psychiatry, and (3) the application of concepts of communication theory and theory of logical types to an interpretation of psychoanalytic practice. The protagonists of the interchange are Gregory Bateson and the two mathematicians Norbert Wiener and John von Neumann; the date, March 1946. This interchange and its sequels are described. While the interchanges between Bateson and Wiener were fruitful, those between Bateson and von Neumann were much less so. The latter two held conflicting premises concerning what is significant in science; Bateson's and Wiener's were compatible. In 1946, Wiener suggested that information and communication might be appropriate central concepts for psychoanalytic theory--a vague general idea which Bateson (with Ruesch) related to contemporary clinical practice. For Bateson, Wiener, and von Neumann, the cross-disciplinary interactions foreshadowed a shift in activities and new roles in society, to which the post World War II period was conducive. Von Neumann became a high-level government advisor; Wiener, an interpreter of science and technology for the general public; and Bateson a counter-culture figure.