This essay reads Olaf Stapledon's Last Men in London through Stapledon's work in academic philosophy. It argues that Stapledon approached history through his work in ethics and aesthetics. The concept of the "telepathic historian" allows Stapledon to explore the dialectic of historical contingency and teleological evolution. Stapledon uses the generic freedom of speculative fiction to explore the inherent paradoxes of knowing the past "as it really was" through telepathy. These paradoxes are demonstrated through a series of ethical tests for Paul, the young man inhabited by the Neptunian telepathic historian. They lead Stapledon to consider a human evolutionary leap forward of, as depicted in his next novel, Odd John.