Albert Einstein T H E B E R L I N Y E A R S : C O R R E S P O N D E N C E , JA N UA RY 1 9 1 9 – A P R I L 1 9 2 0 ENGLISH TRANSLATION OF SELECTED TEXTS Ann M. Hentschel, TRANSLATOR Klaus Hentschel, CONSULTANT Princeton University Press Princeton and Oxford T H E C O L L E C T E D PA P E R S O F VOLUME 9