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he knows have acquainted themselves seriously with these specialties. If you do so
and can convince him of this, he will surely be happy to recommend you.
The results that you arrived at in your diffraction considerations have no relation
to the quantum problem, in my opinion. I could not grasp where you find the formal
kinship.[4]
This nut seems so hard to crack that all your colleagues are wearing
down their teeth on it; I too can sing a sorry tune about
that.[5]
Do not be discontented if you are obliged to devote a large portion of your time
to a practical
occupation.[6]
I also had to do so for a long time and still
do.[7]
I find
that practical tasks protect one from becoming rusty and, contrary to research work,
also give one a certain dose of self-esteem, which is so very necessary in life.
Amicable regards,
89. To Arthur Schoenflies
Berlin, 29 July 1920
Esteemed Colleague,
Pardon me for answering only now; it was impossible for me to get to it
earlier.[1]
The most deserving theoretical physicist to be considered is, without a doubt,
Paul Epstein, presently private lecturer in
Zurich.[2]
His achievements in quantum
theory rank among the best that have been produced in our field in the last ten
years.
Among the colleagues in the specialty whom you have named, I consider Stern
the most suitable. I see his theoretical determination of the vapor pressure of solids
as his most important
accomplishment.[3]
His knowledge is exceedingly multifac-
eted, his critical and pedagogical abilities extraordinary. In addition, he has both the
inclination and a knack for experimentation. I do not think that my excellent opin-
ion of Mr. Stern is essentially influenced by the circumstance that I know him well
personally,[4]
since just a short while ago, Mr.
Bohr[5]
spontaneously spoke in high
praise of him.
Kossel is evidently a very original
mind,[6]
but his publications do not demon-
strate that he has a command of the intellectual tools of theoretical physics. That is
why I do not know whether it is advisable to confer on him the university’s only
chair for theoretical physics. As a teacher he cannot communicate scientific intu-
ition to his auditors but can merely pass on known facts.
Lenz is undoubtedly a capable
theoretician[7]
who has a command of the tools
of his trade. However, I would not consider it fair to place him ahead of Stern.
I surely cannot announce a talk in the field of general
relativity,[8]
because ev-