‘The Materials of Science,the Ideas of Science,and the Poetry of Science’: Warren McCulloch and Jerry Lettvin

This essay explores the relationship between neurophysiologist and cybernetician Warren S. McCulloch (1898–1969) and one of his most important collaborators, neurophysiologist Jerome Y. Lettvin (1920–2011). Lettvin met McCulloch in 1941 as a medical student at the University of Illinois at Chicago, where McCulloch was associate professor of psychiatry. Lettvin recalled that it was McCulloch's influence that led him to study the nervous system; however, theirs was a distinct sort of relationship between mentor and student. According to Lettvin, McCulloch treated young scientists not as children but as if they were experts in any field they happened to be discussing. Both shared an irreverent spirit and ultimately, McCulloch instilled in Lettvin a penchant for theoretical investigations of the nervous system and a humanistic approach to the sciences. By tracing McCulloch's and Lettvin's relationship from their initial meeting in 1941 through to their famous collaborations at MIT's Research Laboratory of Electronics in the 1950s and 1960s, this article highlights the complexities of mentor–student relationships in twentieth-century American science, the personal and intellectual alliances that defined work in cybernetics, and the ‘transdisciplinary’ sorts of practices that characterized cybernetic studies of the brain.