D O C U M E N T 1 3 M A Y 1 9 2 0 2 5 7
ALS. [21 574].
[1]Schlick 1920c.
[2]Henry L. Brose was the translator. A copy of the book is in Einstein’s library.
[3]The German-language edition was Schlick 1920b.
[4]Fritz G. A. Medicus (1876–1956) was Professor of Philosophy and Pedagogy at the Swiss Fed-
eral Institute of Technology (ETH). See Moritz Schlick to Einstein, 22 February 1920 (Vol. 9,
Doc. 327), for his call to the University of Giessen.
[5]Schlick was informed a few weeks earlier that Medicus was not inclined to accept a position in
Giessen (see Moritz Schlick to Einstein, 22 April 1920 [Vol. 9, Doc. 392]).
[6]Peter Debye accepted the professorial position at the ETH on 19 January (see Edgar Meyer to
Einstein, 25 January 1920 [Vol. 9, Doc. 281], note 5).
[7]A reference to the rightist Kapp Putsch of 13–17 March 1920. Among University of Rostock
professors who participated in the Kapp Putsch were Ernst Schwalbe (pathology), Rudolf Helm
(classics), Gerhard Hilbert (theology), and Friedrich Dettweiler (instructor of animal husbandry).
Other Rostock professors of reactionary or ultra-nationalist perspective in this period included Gustav
Herbig (comparative literature and rector of the university), Otto Staude (mathematics), Wilhelm
Walther (church history), and Johannes Reinmöller (dentistry) (see Heitz 1969, pp. 166, 171, and
173–174).
13. To Elsa Einstein
[Katwijk?] Dienstag [11 May 1920]
Liebe Else!
Jetzt ist hier herrliches Wetter. Wir sind viel im Freien und fachsimpeln. Es ist
sehr interessant mit
Ehrenfest.[1]
Gestern war Vorlesung von
Lorentz.[2]
Heute hat
der kleine Paul Ehrenfest Geburtstag. Wir haben feierlich eingekauft. Gestern
Abend b.
Kamerlingh-Onnes.[3]
Die Herren plagen sich auf alle Weise um meine
Ernennung zu
beschleunigen.[4]
Mir pressiert es nicht. So ein Aufenthalterl möcht
ich Euch auch gönnen! Das Geschreibsel ist so unleserlich, weil ich im
Sand[5]
lie-
gend schreibe.
Herzliche Grüsse von Eurem
Albert.
AKS. [143 099]. The postcard is addressed “Frau Elsa Einstein Haberlandstr. 5 Berlin,” with return
address “A. Einstein b. Prof. Ehrenfest Leiden,” and postmarked “[Leid]en 11.V.20 3–4 N[amiddag].”
A postscript by Paul Ehrenfest is omitted.
[1]On Einstein’s stay with Paul Ehrenfest, see Doc. 9.
[2]Hendrik A. Lorentz gave advanced lectures on theoretical physics in Leyden on Monday morn-
ing that were highly acclaimed (see, e.g., Paul Ehrenfest to Einstein, 24 November 1919 [Vol. 9,
Doc. 175], and Jaarboek 1920).
[3]Heike Kamerlingh Onnes.
[4]On Einstein’s appointment as Special Professor at the University of Leyden and its delay, see the
Introduction, sec. III.
[5]Presumably in Katwijk, a seaside village near Leyden.