"Six months after they met... [Jonas] Salk asked [Picasso's ex-lover Françoise] Gilot to marry him...."

"When Jonas proposed, she had replied, 'A relationship would be all right, but I don’t want to get married.... Because I don’t want to live with anybody more than six months a year. That’s it. I need my own time to myself, plus I have my children.' Jonas handed her a piece of paper. 'Write down everything that you don’t want,' he directed. 'I’ll give you an hour.' Françoise proceeded to write down those elements that would make the marriage unsuitable for her. Jonas read it over. 'Very good. It fits my life perfectly.' 'But we don’t know each other,' she cautioned, 'and it may be disastrous because you’re a scientist, and our lives are very far apart.' 'No,' Jonas countered, in what seemed more like a business transaction than a romantic moment, 'even if we’re not so happy, at least we’ll be like a citadel; we’ll be a fortress for each other.' Françoise thought about it. Both felt exhausted by the world and sought a refuge.... Though many could not fathom their marital arrangement, Salk and Gilot’s relationship matured as they grew to know each other better. 'We found new discoveries all the time,' Gilot recalled. And Salk maintained, 'I have achieved in terms of personal relationships as much with Françoise as I could possibly fantasize.'  When asked in an interview how she had ended up with two of history’s most powerful men, Gilot replied: 'Lions mate with lions.'"

From "The Last Love of Jonas Salk/The unusual union of a renowned artist and the discoverer of the Polio vaccine" (Nautilus).