ABSTRACT
In my own case, I came to realize that my research was hampered by a considerable lack of broad knowledge of mathematics. As a graduate student, I had concentrated on logic and foundations so heavily that I had failed to learn enough about lively theories in mathematics proper; overall, I felt a real lack of a mathematics background. Joint work with another active mathematician would, it seemed, help to build up my knowledge. My first experience with joint work, with Virgil Adkisson on point set topology in the 1930s, had brought me into contact with other active topologists. For example, in 1940 I gave a paper on our joint work at the lively conference in topology at the University of Michigan. There, I listened to Wilder, Steenrod, Eilenberg, Whitney, and others, and I realized that I was ready to look for a collaborator or two.
