The stubborn patience that Einstein displayed when dealing with scientific problems was equaled by his impatience when dealing with personal entanglements. So he informed the boy he was canceling the trip. “The unkind tone of your letter dismays me very much,” Einstein wrote just days after finishing his last lecture on general relativity. “I see that my visit would bring you little joy, therefore I think it’s wrong to sit in a train for two hours and 20 minutes.”
There was also the question of a Christmas present. Hans Albert had become an avid little skier, and Mari
gave him a set of equipment that cost 70 francs. “Mama bought them for me on condition that you also contribute,” he wrote. “I consider them a Christmas present.” This did not please Einstein. He replied that he would send him a gift in cash, “but I do think that a luxury gift costing 70 francs does not match our modest circumstances,” Einstein wrote, underlining the phrase.2
Besso put on what he called his “pastoral manner” to mediate. “You should not take serious offense at the boy,” he said. The source of the friction was Mari, Besso believed, but he asked Einstein to remember that she was composed “not only of meanness but of goodness.” He should try to understand, Besso urged, how difficult it was for Mari to deal with him. “The role as the wife of a genius is never easy.”3 In the case of Einstein, that was certainly true.
The anxiety surrounding Einstein’s proposed visit was partly due to a misunderstanding. Einstein had assumed that the plan to have him and his son meet at the Bessos’ had been arranged because Mari and Hans Albert wanted it that way. Instead, the boy had no desire to be a bystander while his father and Besso discussed physics. Just the opposite: he wanted his father to himself.
Mari ended up writing to clear up the matter, which Einstein appreciated. “I was likewise a bit disappointed that I would not get Albert to myself but only under Besso’s protection,” he said.
So Einstein reinstated his plan to visit Zurich, and he promised it would be one of many such trips to see his son. “[Hans] Albert* is now entering the age at which I can mean very much to him,” he said. “I want mainly to teach him to think, judge and appreciate things objectively.” A week later, in another letter to Mari, he reaffirmed that he was happy to make the trip, “for there is a faint chance that I’ll please Albert by coming.” He did, however, add rather pointedly, “See to it that he receives me fairly cheerfully. I am quite tired and overworked, and not capable of enduring new agitations and disappointments.”4
It was not to be. Einstein’s exhaustion lingered, and the war made the border crossing from Germany difficult. Two days before Christmas of 1915, when he was supposed to be departing for Switzerland, Einstein instead wrote his son a letter. “I have been working so hard in the last few months that I urgently need a rest during the Christmas holidays,” he said. “Aside from this, coming across the border is very uncertain at present, since it has been almost constantly closed recently. That is why I must unfortunately deprive myself of visiting you now.”
Einstein spent Christmas at home. That day, he took out of his satchel some of the drawings that Hans Albert had sent him and wrote the boy a postcard saying how much they pleased him. He would come for Easter, he promised, and he expressed delight that his son enjoyed playing piano. “Maybe you can practice something to accompany a violin, and then we can play at Easter when we are together.”5
After he and Mari separated, Einstein had initially decided not to seek a divorce. One reason was that he had no desire to marry Elsa. Companionship without commitment suited him just fine. “The attempts to force me into marriage come from my cousin’s parents and is mainly attributable to vanity, though moral prejudice, which is still very much alive in the old generation, plays a part,” Einstein wrote Zangger the day after presenting his climactic November 1915 lecture. “If I let myself become trapped, my life would become complicated, and above all it would probably be a heavy blow for my boys. Therefore, I must allow myself not to be moved either by my inclination or by tears, but must remain as I am.” It was a resolution he repeated to Besso as well.6
Besso and Zangger agreed that he should not seek a divorce. “It is important that Einstein knows that his truest friends,” Besso wrote Zangger, “would regard a divorce and subsequent remarriage as a great evil.”7
But Elsa and her family kept pushing. So in February 1916, Einstein wrote Mari to propose—indeed, beg—that she agree to a divorce, “so that we can arrange the rest of our lives independently.” The separation agreement they had worked out with the help of Fritz Haber, he suggested, could serve as the basis for a divorce. “It will surely be possible to have the details settled to your satisfaction,” he promised. His letter also included instructions on how to keep their boys from suffering from calcium deficiency.8
When Mari resisted, Einstein became more insistent. “For you it involves a mere formality,” he said. “For me, however, it is an imperative duty.” He informed Mari that Elsa had two daughters whose reputations and chances of marriage were being compromised by “the rumors” that were circulating about the illicit relationship their mother was having with Einstein. “This weighs on me and ought to be redressed by a formal marriage,” he told Mari. “Try to imagine yourself in my position for once.”
As an enticement, he offered more money. “You would gain from this change,” he told Mari. “I wish to do more than I had obligated myself to before.” He would transfer 6,000 marks into a fund for the children and increase her payments to 5,600 marks annually. “By making myself such a frugal bed of straw, I am proving to you that my boys’ well-being is closest to my heart, above all else in the world.”
In return, he wanted the right to have his sons visit him in Berlin. They would not come into contact with Elsa, he pledged. He even added a somewhat surprising promise: he would not be living with Elsa even if they got married. Instead, he would keep his own apartment. “For I shall never give up the state of living alone, which has manifested itself as an indescribable blessing.”
Mari did not consent to give him the right to have the boys visit him in Berlin. But she did tentatively agree—or at least so Einstein thought—to allow the start of divorce discussions.9
As he had promised Hans Albert, Einstein arrived in Switzerland in early April 1916 for a three-week Easter vacation, moving into a hotel near the Zurich train station. Initially, things went very well. The boys came to see him and greeted him joyously. From his hotel, he sent Mari a note of thanks:
My compliments on the good condition of our boys. They are in such excellent physical and mental shape that I could not have wished for more. And I know that this is for the most part due to the proper up-bringing you provide them. I am likewise thankful that you have not alienated me from the children. They came to meet me spontaneously and sweetly.
Mari sent word that she wanted to see Einstein herself. Her goal was to be assured that he truly wanted a divorce and was not merely being pressured by Elsa. Both Besso and Zangger tried to arrange such a meeting, but Einstein declined. “There would be no point in a conversation between us and it could serve only to reopen old wounds,”s he wrote in a note to Mari.10
