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AKS. [122 764]. The postcard is addressed “Frl. Ilse und Margot Einstein Haberlandstr. 5 Berlin,”
and postmarked “Bad Nauheim 24.9.20. 2–3N[achmittags].”
Elsa Einstein. Heinrich Zangger, who also participated in the Bad Nauheim meeting of the
Gesellschaft Deutscher Naturforscher und Ärzte (GDNÄ), took care of her (see Heinrich Zangger to
Michele Besso, 24 September 1920 [SzZ, Nachl. H. Zangger, box 216]).
In all likelihood a reference to Philipp Lenard, with whom Einstein had engaged in a debate on
relativity theory on 23 September at the meeting (see also Doc. 153, note 3).
Earlier in the year, Einstein had proposed to hold a general academic discussion on relativity at the
GDNÄ meeting in his letters to Robert Fricke (Doc. 48) and Arthur Schoenflies (Doc. 89). Following
the much publicized events at the Berlin Philharmonic Hall (see Doc. 111), he challenged all those
who objected to his theory to present their arguments in Bad Nauheim (see Einstein 1920f [Vol. 7,
Some 500 to 600 participants attended the debate in Bad Nauheim’s Bathhouse no. 8 (see Vossi-
sche Zeitung, 24 September 1920, Evening Edition). Seating was limited: at 8.15 A.M., only one door
was opened, “and it was really quite narrow, and made even narrower because to its right and left
stood a mathematician and a physicist—famous people, and not of the most slender build—like
angels with broadswords standing before the Einstein paradise. Entrance to a ‘business meeting’ was
only granted by this mathematical-physical filter to members of the Union of German Mathematici-
ans and the German Physical Society […] until those waiting outside could come in at 9 o’clock. [The
audience] quickly filled up the chairs, stood along the walls and filled the gallery—and waited for the
scholarly dispute” (“und sie war noch dazu recht schmal, und noch schmaler dadurch, daß rechts und
links ein Mathematiker und ein Physiker—berühmte Leute, und nicht vom schlanksten Typ—als
Engel mit den Flammenschwerten vor dem Einsteinparadiese standen. Eintritt erhielten durch dies
mathematisch-physikalische Filter nur die Mitglieder der Deutscher Mathematikervereinigung und
der Deutschen Physikalischen Gesellschaft zu einer „Geschäftssitzung“ […] bis dann um 9 Uhr die
draußen Wartenden eintreten konnten. Man rückte auf den Sitzen zusammen, stand an den Wänden
und füllte die Gallerie—und wartete auf den Gelehrtendisput”; Körner 1921.) The audience still had
to wait for close to four additional hours. Lectures were first given by Hermann Weyl, Gustav Mie,
Max von Laue, and Leonhard Grebe, until finally the floor was opened for a general debate of 15 min-
Lenard, Einstein’s principal adversary, was a prominent and strong critic of relativity (see
Doc. 108, notes 4 and 5, and Doc. 147, note 5). At the meeting, he repeated arguments he had pub-
lished earlier (for the contents of the debate, see Einstein et al. 1920 [Vol. 7, Doc. 46]). Lenard felt
isolated in Bad Nauheim and believed his arguments to be underappreciated (see Lenard 1921,
pp. 36–44, and Schönbeck 2000, pp. 28–33).
Accounts of the debate varied on the particulars, but most agreed and emphasized that it was
matter-of-fact (see, e.g., Vossische Zeitung, 24 September 1920, Evening Edition; Darmstädter Zei-
tung, 29 September 1920; and Deutsche Allgemeine Zeitung, 25 September 1920, Morning Edition).
Nevertheless, tensions had been mounting. Planck, firmly in the chair, had feared beforehand that Ein-
stein might still leave Germany (see Lise Meitner to Max Born, 1 June 1948 [UkCC, MTNR 5/2]).
After the debate, Felix Ehrenhaft and his wife took Einstein for a calming walk in the park, and later
at dinner their party avoided the uneasy company of fellow physicists (see Felix Ehrenhaft, “Meine
Erlebnisse mit Einstein (1908–1940).” DS, MSS 289 B). The debate was further strained by the dif-
ficult relations within the DPG (for Lenard’s role, see Doc. 147). Paul Weyland was also present, yet
remained in the background; for his account, see Weyland 1920d and Vol. 7, the editorial note, “Ein-
stein’s Encounters with German Anti-Relativists,” p. 110.
Einstein was planning to travel to Stuttgart to deliver a lecture at the Schwäbische Sternwarte
Society (see the preceding document). Ernst Levy was a specialist in surgery, gynecology and obstet-
rics in Stuttgart.
Probably a reference to the first line of the poem “Urians Reise um die Welt” by German poet
Matthias Claudius (1740–1815): “Wenn jemand eine Reise thut/So kann er was verzählen.” The poem
was set to music and made popular by Ludwig van Beethoven (Op. 52, No.1).
On their planned trip to Hechingen, see Doc. 149, note 3.