A Mathematical Hermit

Here's a brief article from Science News about Alexandre Grothendieck, who celebrated his 80th birthday in self-imposed isolation in the Pyrenees.

A lot of Grothendieck's work was in a subject known as "category theory." As my Cornell abstract algebra professor once said, he wanted us to learn what a category is the same way we learned what an animal was: by seeing examples of them. (A student then immediately asked the professor what a category was, and he went completely berserk. It was awesome.)