4 0 0 D O C U M E N T S 4 2 1 , 4 2 2 N O V E M B E R 1 9 2 6 421. To Arnold Sommerfeld [Berlin,] 28 November 1926 Dear Sommerfeld, My better self has been fighting a desperate battle against the lazybones in me. But because the better self is smarter and—weaker, it has capitulated, so now I cannot generate the steam for the lecture in Munich.[1] You can imagine from its length how sustained the above-mentioned battle was. The successes of Schrödinger’s theory make a great impression,[2] and yet I do not know whether it involves more than the old quantum rule, i.e., something that ¢does justice to² corresponds to one aspect of real occurrence. Has one really come closer to the solution of the puzzle? I am sending you a small paper, which is actu- ally nothing more than a pretty burial place for a former hope.[3] That book by Eddington[4] really is extraordinarily brilliant. But I cannot en- dorse the tendency to interpret natural laws only as ordering schemes that distin- guish between cases falling within them and ones that don’t. The objection must also be raised that he emphasizes too much the logical necessity of relativity theory. God could also have decided to create an ether that is absolutely at rest in- stead of the relativistic one. This applies particularly when he is supposed to have set up the ether in De Sitter’s (essential) independence of matter, to which belief Eddington actually is inclined [5] then an “absolute” function is also attributed to the ether. It is remarkable that in most minds there is no organ for the evaluation of this state of affairs. Best regards, your A. Einstein 422. From Max Born Göttingen, 30 November 1926 Dear Einstein, My wife told me that you apparently enjoyed her play when she read the first act to you.[1] She has now revised the whole thing and improved it I think it has indeed become better. Now comes the problem of trying to have it performed at a reputable theater. It would be very good for Hedi’s mindset if it succeeded. She already has a hard enough time living out her literary inclinations without neglecting her duties