## Thursday, November 21, 2013

### Speaking of mathematics

My father spent his adult life as a mechanical engineer. Here is a picture (thanks Tom) of Dad graduating with an engineering degree from the University of Tennessee in Knoxville. The young woman with him is his sweetheart from across the street in Chattanooga, soon to be his bride, later my mother.

For most of his engineering career, Dad did quality control for the American Lava Corporation, makers of electrical insulators, making of himself something of a pioneer in his field. Retiring at age 60, he took a job at Chattanooga's Notre Dame High School as plant manager and teacher of geometry. This last was dear to his heart.

I have enough of his genes and nurture to know why. Geometry -- yes, high-school geometry -- is a beautiful subject. "Beauty bare," Edna St. Vincent Millay called it. Begin with the obvious and unwrap the wonderful. The subject, of course, began with Euclid, whose book on geometry is still worth reading. Only a century ago Euclid's text was still used in schools. As an adult, I once worked my way through Book I of The Elements, which begins with ten presumably self-evident Postulates and Common Notions (e.g. "If equals are added to equals the wholes are equal."), and ends with Proposition 47, the mystically amazing and not-at-all-obvious Pythagorean Theorem.

Dad wanted to write a plane geometry textbook for high school students. He started with the definition of a point. That was as far as he got. Cancer had a point to make, and the point was final.

His life was Euclidean, in a way. It began with certain givens, axioms and common notions, nature and nurture (the sorts of things apparent in the photographs from Aunt Charlotte that Tom has digitized), then unfolded with a kind of mathematical inevitably. Each event followed from the ones before. He never went off the rails. He never rolled the dice.
Euclid alone
Has looked on Beauty bare. Fortunate they
Who, though once and only then but far away,
Have heard her massive sandal set on stone.