I read Sylvia Nasar’s biography of John Nash, *A Beautiful Mind* (1998), which also has been made a movie. John Nash won the Nobel in economics in 1994, but is equally famous for his serious mental disorders which he recovered from in the early nineteen ninties. ‘B squared + RTF = 0’ is a ‘very personal’ equation Nash used, while he was ill, to describe his life when he was at MIT (see chapter 21, *A Beautiful Mind*). Of course, he used an equation to describe his life. ‘The equation represents a three-dimensional hyperspace, which has a singularity at the origin, in four-dimensional space. Nash is the singularity, the special point, and the other variables are people who affected him’ Sylvia Nasar writes about the equation. Sometimes, I recognize something of myself in the Nash Nasar describes, bar the genius, of course. I have not come to the point where I feel like describing my life with an equation, though, and if I do, it probably won’t be four-dimensional.

Nash did marvelous mathematical research at MIT, but he also lead a chaotic life. My life is quite marvelous most of the time; my research, however…