The name of Paul Bernays (1888-1977) is familiar probably first of all for his contributions to mathematical logic. Many of those were in the context of his position as David Hilbert's junior collaborator in his proof-theoretic program inaugurated after the first World War. For those of us starting out in logic in the mid-twentieth century, the monumental Grundlagen der Mathematik of Hilbert and Bernays was one of the basic works in mathematical logic that we were obliged to study. That was the more true for those like me who aspired to work in proof theory.

Bernays' collaboration with Hilbert ended with the publication in 1939 of volume II of that work. Because the Nazis had forced his removal from his position in Göttingen in 1933, the collaboration ceased to be face-to-face in 1934, when Bernays moved to Zürich, where he lived for the rest of his life.

Bernays is also known, though less well known, as a philosophical writer. The fact that he had some philosophical training was apparently a reason why Hilbert chose him as his collaborator. Constance Reid tells the story that when Hilbert visited Zürich in 1917, he went for a walk with two local mathematicians, Bernays and Georg Pólya. The conversation turned to philosophy, and although Pólya was usually rather voluble and Bernays was not, this time Bernays did most of the talking. On the spot Hilbert invited Bernays to Göttingen to work with him, and Bernays accepted.