I had drawn up a list of scientists of both East and West and had written to them, enclosing the statement, shortly before I went to Rome with the Parliamentarians. I had, of course, sent the statement to Einstein for his approval, but had not yet heard what he thought of it and whether he would be willing to sign it. As we flew from Rome to Paris, where the World Government Association were to hold further meetings, the pilot announced the news of Einstein’s death. I felt shattered, not only for the obvious reasons, but because I saw my plan falling through without his support. But, on my arrival at my Paris hotel, I found a letter from him agreeing to sign. This was one of the last acts of his public life.
Bertrand Russell: Autobiography