8 6 D O C U M E N T S 7 7 , 7 8 S E P T E M B E R 1 9 2 5 77. To Paul Ehrenfest Berlin, 25 September 1925 Dear Ehrenfest, You write me that there is a professorship of theoretical physics to fill in Utrecht and ask me whom I consider to be qualified among the physicists who do not yet hold a professorship. I have rarely been asked about such matters without the question triggering much doubt and worry. However, this time, it is easy for me. According to my firm conviction, Kramers, and only he, is entitled to this posi- tion. I believe I would favor Kramers even if the candidates from all countries were to be compared. For he, along with Bohr, has certainly performed the most import- ant theoretical work on the topics that are currently the focal point of physicists’ interests. If Kramers were not considered to be the front runner in his own native country, all the experts would certainly find it incomprehensible. Warm regards from your Einstein 78. To Eduard Einstein [Berlin, ca. 26 September 1925] Dear Tete, Your little poems gave me much joy and have even been duly recognized by the expert word-smith language abuser and rhyme rattler, Moszkowski. Keep your humorous attitude later in life, too. Because very few human matters are en- durable without humor. They even lose some of their ludicrousness through laugh- ter. I am currently conducting such nice experiments on the crawling of oils along metal surfaces. You would have a lot of fun with that. When I come to see you both again, I’ll show it to you. All you need is knitting needles, kerosene, concentrated alcohol, a thin wire, perhaps from a burned-out light bulb. I have a lot of work to do but not really major things. It pleases me very much when I hear anything from you it doesn’t have to be poetry. A papa like me is pleased with everything. Warm regards & kisses from your Papa Best regards to Albert.