After his death, according to his biographers - Evlanoff and Flour, and Fant - Nobel's letters were locked within the Nobel Institute in Stockholm and became the best kept secret of the time.

他逝世后，为他撰写传记的作家Evlan of f把他的信件锁在设在斯德哥尔摩的诺贝尔学院，并得到了妥善的保管。