Lecturer in 1969. He was president of the Mathematical Association of America, 1965–1966, which awarded him its Distinguished Service Medal in 1973. He was elected to the American National Academy of Sciences in 1963. Brown University (1958) and the University of Michigan (1980) awarded him honorary doctorates. The mathematics department at the University of California annually bestows one or more graduating seniors with an award in Wilder's name. The historical, philosophical, and anthropological writings of Wilder's later years suggest a warm, colorful personality. Raymond (2003) attests to this having been the case. For instance: "[Wilder] was a devoted student of southwestern Native American culture. One day he told me that after retiring he would like to be a bartender in a rural area of Arizona or New Mexico, because he found the stories of the folk he met in bars there so fascinating." The topologist Wilder's thesis set out a new approach to the Schönflies programme, which aimed to study positional invariants of sets in the plane or 2-sphere. A positional invariant of a set A with respect to a set B is a property shared by all homeomorphic images of A contained in B. The best known example of such a positional invariant is embodied in the Jordan curve theorem: A simple closed curve in the 2-sphere has precisely two complementary domains and is the boundary of each of them. A converse to the Jordan curve theorem, proved by Schönflies, states that a subset of the 2-sphere is a simple closed curve if it: Has two complementary domains; Is the boundary of each of these domains; Is accessible from each of these domains. In his "A converse of the Jordan-Brouwer separation theorem in three dimensions" (1930), Wilder showed that a subset of Euclidean 3-space whose complementary domains satisfied certain homology conditions was a 2-sphere. Around 1930, Wilder moved from set-theoretic topology to algebraic topology, calling in 1932 for the unification of the two areas. He then began an extensive investigation of the theory of manifolds, e.g., his "Generalized closed manifolds in n-space" (1934), in effect extending the Schönflies programme to higher dimensions. This work culminated in his Topology of Manifolds (1949), twice reprinted, whose last three chapters discuss his contributions to the theory of positional topological invariants. The philosopher During the 1940s, Wilder met and befriended the University of Michigan anthropologist Leslie White, whose professional curiosity included mathematics as