7 2 0 D O C U M E N T 4 3 2 F E B R U A R Y 1 9 2 3 [2]The correct date is 1 July 1920 (see 23 June 1920 in Vol. 10, Calendar). [3]See 15 March 1921 in Vol. 12, Calendar. 432. From Nicholas M. Butler[1] [New York,] February 26, 1923 My dear Professor Einstein: On behalf of Columbia University, I have the honor formally to invite you to ac- cept appointment to a Professorship in the Faculty of Pure Science of this Univer- sity.[2] The duties and occupations of the Professorship will be precisely what you wish to have them. Our aim will be to make it easy and convenient for you to pursue your personal studies and course of reflection without onerous academic or public burdens of any kind. When you wish to give academic lectures, either singly or in a connected series, full opportunity will offer. When you wish to confer with ad- vanced students of mathematical and physical science or to hold a seminar, that can be quickly arranged. All these matters, however, are for your own determination, since it is our firm belief that your greatest contributions to science will be made if you are set free to work in your own way, without responsibility of any other kind. The annual salary of the Professorship is $10,000, or about 40,000 gold marks. The term of service may begin at your convenience, but October 1, 1923 is suggest- ed, if that should seem a suitable time to you. We realize the questions which may arise in your mind and in the mind of Mrs. Einstein concerning this invitation. America is, however, and is likely for some time to remain, a quieter place than Germany for the pursuit of scholarship. More- over, science is international and few things would contribute more powerfully to advancing the influence of German science and to restoring it to its old place in American opinion than your presence in the United States. You would stimulate the higher study of mathematical and physical science on every side. We feel that a new era in our scientific development would open if you were to become resident among us as an inspiring and impelling intellectual force. During your recent visit to America you made many friends, all of whom would welcome you and Mrs. Einstein back to this country. You might make your home wherever you liked, either here in New York as you are now in Berlin, or in some quiet place in the country near by, if that should seem to you more agreeable. I wish to put this invitation before you on behalf of Columbia University with all possible urgency, and to beg you to accept it in the interest of science, of inter- national comity, and, I trust, of the most successful prosecution of your own per- sonal work.