I N T R O D U C T I O N T O V O L U M E 1 3 x l i i i asked Einstein to add an outline on general relativity. Einstein refused permission to publish the decade-old manuscript, telling Marx: “Sorry, I cannot agree, it is far too outdated” (Doc. 66). The theory of relativity had indeed matured since its completion in late 1915. Many of Einstein’s colleagues had chimed in and had begun to further develop the theory, investigating solutions to its field equations, writing technical or popular expositions, and advancing its conceptual interpretation. Einstein welcomed his colleagues’ efforts, lent them his support, or gave them his constructive criticism. In February 1922, he published a short review in Die Naturwissenschaften of Wolfgang Pauli’s article “The Theory of Relativity” that had appeared in the Ency- klopädie der mathematischen Wissenschaften. Einstein highly praised Pauli’s ex- cellent overview of his special and general theory in Einstein 1922e (Doc. 62). He also endorsed a textbook on relativity by the Viennese physicist Hans Thirring by contributing a brief preface for its French translation (Doc. 234). The dissemination of relativity theory and the debates surrounding it continued to concern Einstein, evident both in his public statements and in correspondence. In letters to Hans Reichenbach, Einstein expressed his general agreement with Reichenbach’s analysis of the philosophical implications of relativity and praised its clarity (Docs. 119 and 366). During his visit to Paris, on 6 April 1922, Einstein participated in a discussion on relativity that took place at a meeting of the Société française de Philosophie (Einstein et al. 1922, Doc. 131). The participants at this meeting included almost all the leading French mathematicians (such as Jacques Hadamard, Elie Cartan, and Paul Painlevé), physicists (such as Paul Langevin, Jean Perrin, and Jean Becquerel), and philosophers (such as Henri Bergson, Emile Mey- erson, and Léon Brunschvicg). Among Einstein’s numerous presentations and lectures on relativity, one is of particular significance. During his stay in Japan, on 14 December 1922, Einstein attended a student re- ception at Kyoto University.[7] He was asked by the students to talk about how he had found the theory of relativity, and complied with this request in an extempora- neous lecture (Doc. 399). Unfortunately, no handwritten notes about this lecture are preserved. But Einstein’s friend, guide, and translator Jun Ishiwara published a version of Einstein’s lecture from the notes he had taken in Japanese. Although Ishiwara’s Japanese version of Einstein’s impromptu lecture is only an indirect ac- count of what Einstein actually said, it nevertheless records one of Einstein’s most explicit reminiscences concerning his creation of the theory. Ishiwara’s text has played a prominent role in debates about the genesis of the theory of relativity, in particular with respect to the controversial role of the Michelson-Morley experi- ment in Einstein’s early thinking. Unfortunately, the Japanese text is ambiguous about this particular question, and several English translations have been published