Variety improves the things that we do too often, but it rules the things that we don't do often enough.

Psychologists call this habituation, economists call it declining marginal utility, and the rest of us call it marriage.

Arthritic toothless people who love orgasms are more likely to reproduce than are limber, toothy people who do not.

Few of us can accurately gauge how we will feel tomorrow or next week. That's why when you go to the supermarket on an empty stomach, you'll buy too much, and if you shop after a big meal, you'll buy too little.

We humans can look deep into future and predict what will happen, but then turn around and do nothing about it.

My friends tell me that I have a tendency to point out problems without offering solutions, but they never tell me what I should do about it.

I have everything that I could possibly want in life, from a gorgeous granddaughter and a wonderful wife, brilliant students, the best job anyone could hope for, and about half of my hair. Not the half I would have kept, but no one consulted me.