Once when I was teaching a composition class at the university, I flew back from New York for class and neglected to get back on Central Standard Time. I came bustling into the classroom and walked to the front, took off my coat, set my briefcase on the table, smiled at the students assembled, and was about to open my mouth and start talking about the importance of structure in comic writing and then something struck me as Not Right. Familiar faces were missing. I leaned down and said to a girl in the front row, "This isn't composition, is it." She said, "No, it's math." "Good," I said. "That's what I thought." And picked up my briefcase and coat and headed for the exit, as a young man with a crewcut and clear-rimmed glasses arrived and set his briefcase on the table. He was the math guy. Not me. And he knew more about structure.

A simple mistake, one that anyone could make, and isn't that true of all of them? Divorce, episodes of lousy parenting, dumbhead investments, negligence behind the wheel - it's all too human, and you have to learn how to admit failure and walk away from it and not torment yourself. Sometimes the remorse is worse than the offense.

It is invigorating to realize you've been dead wrong about something. That's why we read history. It's an antidote to smug self-righteousness, which makes us insufferable. You learn about this from books. I can't think of any movie or song that changed my mind about anything, but books of history certainly have.

You sit down and read about the temperance movement of the 19th century, which brought about Prohibition, which you always thought was a foolish attempt by blue-nosed puritans to repress bonhomie, which was the view of the satirists of the Twenties, but there is another point of view: The temperance cause was a protest movement by women who, having been shut out of higher education and relegated to menial jobs, were economically dependent on men and therefore terribly vulnerable to a man's alcoholism. The temperance crusader Carrie Nation, famous for busting up saloons with a hatchet, was the wife of a raging alcoholic who had destroyed her life. The Women's Christian Temperance Union, which you had thought of as a joke, has certain heroic dimensions and helped pave the way for women's suffrage.

It's good for an old liberal like me to read history and recognize that Eisenhower was no dolt and Adlai Stevenson was no giant. And to read about Joe McCarthy and realize that, opportunist and blowhard that he was, he was hardly the embodiment of evil that we liberals cherished as an enemy. ...