John Horton Conway died on April 11 of COVID-19. He was 82 years old. In the midst of social distancing measures to fight the coronavirus pandemic, a common refrain is “life goes on”. But sometimes it doesn’t.

Conway was an emeritus professor at Princeton University. Among mathematicians, he was known for his breadth and cleverness, as well as his personality and his seemingly infinite curiosity. In MathSciNet, a bit over one quarter of his papers are in number theory, about a sixth in group theory, and a tenth in convex or discrete geometry. The rest are dispersed about 20 other classes in the MSC. Conway managed to make lasting contributions in those other 20 areas, such as his work in algebraic topology and knot theory, where he has an invariant named after him: the Alexander-Conway polynomial. Meanwhile, behind the scenes, Conway was frequently contributing puzzles, games, and ideas to Martin Gardner, who would write about them in his famous column in *Scientific American*.

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