4 4 D O C U M E N T S 2 5 , 2 6 J A N U A R Y 1 9 2 2 25. To Max Born and James Franck [Berlin,] 18 January 1922 Dear Born and dear Franck, Heavy-heartedly, I do have to cancel after all. But there is no other way. I am so behind with written and other obligations that I cannot in fact afford that esca- pade into the El Dorado of scholarship. So I shall have to bring my homage to Hil- bert in writing. Also tell Courant, who wanted to engage me as a minstrel. Laue is fiercely fighting my experiment, or rather my interpretation of the same. He claims that the undulatory theory does not require any bending of rays at all. He suggested a nice experiment for analyzing possible undulatory ray bending with capillary waves, which exhibit strong dispersion, of course, to replace the theory which is so hard to reach with the required rigor. There was a grand dispute at the colloquium today already. Next time, continuation. Don’t be annoyed delayed does not mean declined. With cordial regards, also to your wives, yours, A. Einstein. Mrs. Born, hearty thanks for the sweet little picture. One evening recently I read out to Laue and Vegard all the verses you had dedicated to us and enthralled them everyone thought them a sensitive rival to Master Busch. Out of consider- ation for the little quarrel we had, I send you my special greetings. 26. To David Hilbert [Berlin,] 18 January 1922 Esteemed Colleague, I had already quite firmly decided to offer you, in person, my hearty congratula- tions on accomplishing that period of life. But now it absolutely does not work out because I cannot leave. I can only grasp in a more restricted (and indolent) fash- ion a mere fraction of your immense life-work, but just enough to divine the frame- work of your creative mind. Add to that the humor and secure, independent view on all things and—a uniquely hard skull, besides two strong arms to clear the dung out of the faculty stall from time to time. I wish from my heart that you will con- tinue with energy and in good spirits to guide and perfect, as you should, the grand work of art that you have shaped of your life, with the joy and ease with which you have hitherto proceeded. Amen. Cordial greetings to you and your wife, yours, A. Einstein.