2 2 D O C U M E N T 3 J A N U A R Y 1 9 2 1
Date based on New Year’s greetings and on reference to Zangger’s trip to Paris in Hermann Weyl
to Heinrich Zangger, 1 January 1921 (SzZ, Nachlass H. Zangger, box 406).
Einstein had attended the 86th meeting of the Gesellschaft Deutscher Naturforscher und Ärzte
in Bad Nauheim from 21 to 26 September 1920 (see Einstein to Ilse and Margot Einstein, 24 Septem-
ber 1920 [Vol. 10, Doc. 154]). For more on the events that took place there, see Vol. 10, Introduction,
Presumably Zangger 1920.
The book argued that medicine and law need to cooperate in order to reduce endangerment and
damage to others through neglect or willful actions (Eliasberg 1951, p. 317).
It was only in 1882 that the microbe causing tuberculosis, the disease with the highest mortality
rate at the time, was first identified. Most of the advances in understanding typhoid, the third deadliest
disease in the early twentieth century, took place from 1903 to 1915, when it was determined that
some people had recovered, and that some “carriers” who had never suffered could still be contagious
(Fenster 2003, pp. 106–120).
Einstein had seen his son Eduard in early October 1920 when he vacationed with his boys in
Benzingen (see Einstein to Elsa Einstein, 19 October 1920 [Vol. 10, Doc. 179]). Zangger was one of
Eduard’s doctors when he had been ill with a pulmonary ailment (see, e.g., Einstein to Heinrich Zang-
ger, 19 April 1920 [Vol. 9, Doc. 380]).
Hermann Weyl (1885–1955) was Professor of Mathematics at the Swiss Federal Institute of
Technology. On his severe asthmatic attacks, which forced him to take frequent sick leave, see Frei
and Stammbach 1992, p. 50, as well as Einstein to Elsa Einstein, 14 July 1919 (Vol. 9, Doc. 70b, in
Vol. 10). Robert Gnehm (1852–1925) was president of the Swiss School Council (Schweizerischer
On Einstein’s objections to Weyl’s unified theory of gravity and electromagnetism, see, e.g.,
Einstein to Michele Besso, before 26 July 1920 (Vol. 10, Doc. 85).
Because Weyl’s unified field theory made no firm prediction concerning the existence of a grav-
itational redshift, a number of prominent physicists had proposed it as a successor theory to general
relativity if the latter theory were falsified by the solar redshift measurements, as still seemed possible
in early 1921. For instances of this viewpoint, see Adriaan D. Fokker to Einstein, 26 July 1919 (Vol. 9,
Doc. 75), and Max Born to Einstein, 16 July 1920 (Vol 10, Doc. 75).
Already in the third edition of his textbook, Weyl had revised and expanded the final sections,
discussing his unified field theory (Weyl 1919). In the newly published expanded fourth edition, Weyl
had further revised sections 32 and 36, expounding against Mie’s field theoretic theory of matter his
own theory “according to which matter appears as a limiting singularity of the field, but charge and
mass appear as fluxes of force in the field” (“nach welcher die Materie als Grenzsingularität des Fel-
des erscheint, Ladung und Masse aber als Kraftflüsse des Feldes”; Weyl 1921, p. vii).
Born 1920. After discussing the foundations and historical origins of geometry, mechanics, cos-
mology, optics, and electrodynamics in the first five chapters, it is only in the concluding two chapters
that Born deals explicitly with Einstein’s special and general theories of relativity.
Rolland (1866–1944), the French writer, with whom Einstein had corresponded since 1915.
3. To Hendrik A. Lorentz
[Berlin,] 1. I. 21.
Verehrter Herr Kollege!
Erfreut und beschämt stand ich vor Ihrer Sendung, erfreut, weil Sie an uns dach-
ten, beschämt, weil Sie so viel Mühe hatten. Und dabei geht es hier entschieden
besser mit der Nahrung. Überhaupt macht es den Eindruck, dass wir langsam wie-
der einer besseren Zeit entgegengehen.—