Introduction ALBERT EINSTEIN'S secretary during the last twenty-seven years of his life, Helen Dukas, and his close collaborator, Banesh Hoffman, had, not very long ago, a delightful little Einstein tale to tell. According to them, a prominent American publisher, whom they chose not to identify, had just broken ground for a new library wing for his country home and wanted to place in the cornerstone an airtight metal box containing items that would be of considerable archaeological interest to the coming generations. Thus, one of the items intended to be interred in this Time Capsule was to be an issue of The New York Times printed especially for this purpose on long-lasting rag paper The publisher wanted Einstein also to contribute a message for posterity and to this end sent him a sheet of this very special paper which he said was expected to last for a thousand years.