D O C . 3 9 5 A P R I L 1 9 2 0 3 3 1 mainly for three reasons: because one or two points could be of interest to you sec- ond, because I am glad to help make the theory of relativity known among all cir- cles and third, because I do not see a finer means of drawing nations closer again. Besides, you could perhaps just ask Dr. Freundlich to attend to the letter if you could thus save time and effort. With cordial greetings to you all, I am yours very truly,[6] Oppenheim. 395. From Hans Vaihinger Halle-on-S[aale], 15 Reichardt St., 24 April 1920 Highly esteemed colleague Einstein, Thank you very much indeed for your friendly letter of the 12th of this mo., in which you extend the prospect of appearing for the convention of those interested in positivistic idealism along the lines of the Philosophy of As If, under the precon- dition that you are in Berlin at the time of the meeting.[1] The convention is sched- uled for May 29 (Saturday), whereupon the plenary session of the Kant Society di- rectly follows on Sunday, May 30.[2] Anyone taking part in the 1st meeting can return to Berlin on Saturday evening, of course, but every participant of the first session is likewise invited and welcome as a guest of the Kant Society on Sunday. The meeting on Saturday (briefly denoted the “As If Conference”) looks to be a significant success, as can already be gathered from the various registrations. I am enclosing at the same time a draft of the circular that will be sent out in about 2500 copies as printed matter with reply.[3] Of these, 2200 copies are going to the mem- bers of the Kant Society, at the same time as the invitation that the latter is issuing for its own convention on Sunday. Everything is already settled with Professor Liebert.[4] By the way, I am going to change the draft a little and place the debate about the theory of relativity at the start. This matter is already exciting the liveliest interest among local academic cir- cles, particularly among mathematicians and scientists. Incidentally, it will be pos- sible to offer private accommodation with members of the university to the external participants and for you especially I would like to have or find, resp., suitable pri- vate accommodations. Our colleague Mie may see it as an honor to have you as his guest.[5] Perhaps you can let me know your wishes in this regard, or resp[ectively], the names of those with whom you are in contact and to whom I could turn. As I gather from the papers, you are now leaving for Holland and will travel to Norway at the beginning of June.[6] This would fit very well, of course. Then you will be able to come very comfortably to Halle and back on Saturday the 29th. In Christiania you will find grateful listeners. I am familiar with Norway and the