My daughter Mariah used to have a Spanish teacher who would quell a restive class by commanding them to “press the pause button!” They all knew what he meant, and it (sometimes) worked. I’ve often wanted to try something like that myself — not with noisy teenagers, but with my life. With committee work, administrative duties, teaching, grading, reading, and writing, sometimes I lose track of myself for a while and simply move on automatic pilot. When that happens it’s time to “press the pause button.”

When I think back to the one day that almost everyone in my generation recalls vividly, I remember that the one thing that gave me perspective on September 11, 2001 was the fact that I taught my class in College Algebra. When my students were having trouble making it to class, because of closed bridges and highways, I stood in front of a (small) class and explained the rules by which the mathematical world, if not the real world, functioned.