D O C U M E N T S 2 4 7 , 2 4 8 J U N E 1 9 2 2 2 0 1 247. From Eduard Einstein [Zurich, after 24 June 1922][1] Dear Papa, I’m already stuck in the middle of school again now but it’s not all that bad, we have a substitute teacher who simply keeps us busy, but we aren’t learning a thing. Yesterday, e.g., during arithmetic class I proved the Pythagorean theorem all by myself, namely, like this: The 4 triangles are congruent (4th congruency th.), consequently: cancels out and the squares remain. Otherwise there isn’t much of interest. The weather is much worse than in Berlin. Many greetings from your Teddy. 248. From Mileva Einstein-Maric [Zurich, after 24 June 1922][1] D[ear] A[lbert], I hope my last letter made it to you! Albert would be very happy if he were allowed to travel with you and I would like to grant him this favor so much that I join his plea and again ask you to please take him along.[2] It would be as I sug- gested to you, that is, that he do his praxis in the summer, certainly not a wasted year for him and he would surely also profit very much from being with you. So we ask you, please! Mainly also for a prompt reply. A prof. from Belgrade asked me whether it was true that you plan to deliver lec- tures in B. for the benefit of starving Russians. Do you know anything about that? From another quarter I happened to hear that you are among those people whom certain elements—I don’t know which—are plotting against, like against Rathenau.[3] I’m shocked! Must you really be living there when everything is so unstable and insecure? I found this news horrifying. Please answer Albert as soon as possible. K[in]d regards, M[ileva]. c2 a b)2 + ( + 2ab – = a b)2 + ( a2 2ab b2 + + =