In my March diary on NRO last week I had occasion to mention the great

geometer H.S.M. “Donald” Coxeter. He died on Monday at the age of 96.

There is an obit in today’s Daily Telegraph, & I imagine in the Canadian papers, too:

This is not just the loss of a

fine mathematician, but a blow to geometry itself. Non-mathematicians are,

I guess, not aware of the fact, but geometry is deeply out of favor in

modern universities. It is quite common for a university math department,

even a “strong” one, to teach no geometry at all. This is a great shame,

as geometry is not only beautiful and fascinating in itself, but has

nourished the imagination of great mathematicians to such a degree that the

history of math–I would almost go so far as to say “the history of Western

thought”–cannot really be understood without some acquaintance with

geometry. What, after all, was the inscription over the door of Plato’s

Academy? Ageometretos medeis eisito–”Let no-one ignorant of geometry

enter.” Coxeter kept this flame alive. If you like geometry, or think you

might want to know more about it, buy his great and very accessible classic

book, Introduction to Geometry