Einstein's marital difficulties 'in the age of quantum theory'.

Einstein conveys his profound gratitude for the support Besso gives to his wife and children, and expresses alarm at the news of the health of his wife, Mileva: 'According to your letter, my wife really seems to be seriously ill'. He has decided (in a passage omitted from the published text) not to come to Zurich, in part in order to avoid a confrontation with his wife, and in part because his relations with the children during his visit at Easter had worsened so much that his presence would not be helpful: if Mileva has to go to hospital, he will meet the children somewhere where they can spend the holidays. He goes on (in a passage which is also omitted by the editor) to enlarge on his difficult relations with Mileva – comparing himself to a child who has been once bitten, twice shy – and doubting whether her illness is even real; he goes on to say that if he had not found the strength to separate from Mileva it would have destroyed him physically and mentally. The letter concludes however on a humorous note: 'I beg you to keep me informed of the situation by means of postcards, without paying too much attention to any continuity of content. In the age of quantum theory, this is perfectly permissible'.