I N T R O D U C T I O N T O V O L U M E 1 2 x l v i i
informed by “a competent (socialist) source” that it was “party-political in charac-
ter” (Docs. 226, 231, 234). Given Einstein’s close ties to high-ranking socialist pol-
iticians, such as Konrad Haenisch and Carl H. Becker, he may well have turned to
them for an assessment of the various appeals he received in regard to the
famine.[51]
V
Overwhelmed by the demands on him, Einstein wrote to an old associate that he
was displeased with his hectic life, and that he barely had an opportunity for
“reflection.” For him, science was “the utmost” (“das Schönste”). Although he
mused that his own “inventing on a grand scale” might be over (Doc. 105), by
December he exulted that an experiment designed to probe the process of light
emitted by canal ray particles, on which he had been working for several months,
had given him his “strongest scientific experience in years” (Doc. 345). Despite the
lack of uninterrupted time for work, during 1921 he engaged in important theoret-
ical and experimental investigations and published at a steady pace. Otherwise,
with some notable exceptions, he confined himself in public and in print mostly to
brief statements on political or other issues. He also published a great deal: his lec-
ture to the Prussian Academy of Sciences on “Geometry and Experience,” dealing
with a broader analysis of the mathematical and physical assumptions and implica-
tions of relativity theory (Einstein 1921c [Vol. 7, Doc. 52]); and further papers on
general relativity (Einstein 1921e [Vol. 7, Doc. 54]), on the size of globular star
clusters (Einstein 1921f [Vol. 7, Doc. 56]), and on a proposed experiment on the
nature of light (Einstein 1922a [Vol. 7, Doc. 68]). He wrote for the popular press
on relativity (Einstein 1921d [Vol. 7, Doc. 53]), clarified in print his views on Zion-
ism (Einstein 1921h and Einstein 1921j [Vol. 7, Docs. 57 and 62]), pacifism (Ein-
stein 1922b [Vol. 7, Doc. 69]), and economic deprivations (Vol. 7, Doc. 65, and
Einstein 1921k [Vol. 7, Doc.70]), and drafted expert opinions on patent disputes
(Vol. 7, Docs. 66 and 67).
Einstein’s theory of relativity was increasingly becoming part of the public un-
derstanding of modern theoretical physics. It also influenced broader philosophical
debates on the nature of space and time and on the characteristics of scientific re-
search. While still fully engaged in popularizing what had been accomplished in
this area, Einstein still continued to work on unsolved problems associated with the
theory.
One of these open questions concerned the role of the electromagnetic field.
Like other theoreticians at the time, Einstein believed that a satisfactory physical
theory should account for both the gravitational and the electromagnetic field in a