x l i i I N T R O D U C T I O N T O V O L U M E 1 6 While disinclined to be as politically engaged as in previous years, Einstein advocated for domestic legislative reform, for gay and minority rights, and for European rapprochement, and he avidly supported conscientious objection to mil- itary service. He resigned officially but not publicly from his positions at the Hebrew University yet continued to carry out an intense correspondence with Chaim Weizmann and to support Jewish institutions and causes both in the Dias- pora and in Palestine. Honors and invitations continued to arrive unabated. In an important prelude to his eventual emigration to the United States, he was invited in September 1927 to accept a research professorship at Princeton University (Doc. 52). He declined the offer, citing his age: “An old plant should stay put, because otherwise it dies” (Doc. 55). Einstein was elected foreign member of the Royal Society of Edinburgh, the Royal Irish Academy, and the Swedish Academy of Sciences. He received honor- ary doctorates from the University of Cambridge and the Sorbonne. He himself nominated Arthur Compton for the Nobel Prize in Physics in 1927. But he never finalized nor sent a draft nomination for 1928, in which he proposed in various combinations Louis de Broglie, Clinton J. Davisson, Werner Heisenberg, Erwin Schrödinger, Max Born, and Pascual Jordan (Doc. 271). He resisted his friend Paul Ehrenfest’s urging to nominate Paul Langevin and Pierre Weiss (Doc. 137) and re- jected repeated efforts to engage his support for the nomination of Sigmund Freud for the Nobel Prize in Physiology or Medicine, steadfast in his lack of conviction in the “truth content” of psychoanalysis (Docs. 148, 301). The present volume, like the previous one, covers two years, but contains some 1,600 letters by and to Einstein, many more than the previous period. Some of the increase can be attributed to the fiftieth birthday congratulations Einstein received and acknowledged. As a prelude to his approaching fiftieth birthday in March 1929, he had only one wish: to escape the press, the visitors, the fanfare, and the tributes. But some of the increase is certainly due to the efficient handling of cor- respondence by Dukas, who maintained carbon copies in his files. Nevertheless, the steady rise in incoming requests and inquiries, administrative correspondence, and exchanges with publishers would continue over the next decade of his life. Among the 114 writings comprising poems, obituaries, addresses, book reviews, cosigned appeals, political statements, and responses to various inquiries meant for publication there are some 30 scientific articles, mostly addressed to a general audience. But there are also 6 scientific papers published in the proceedings of the Prussian Academy of Sciences that deal with unified field theory and the problem of motion. The volume also contains a significant number of items that belong to an earlier period, 28 of which are presented as full text and 30 in the Calendar of Abstracts.