Anyone who has ever taught at a college or university must have had this experience.

You’re in the middle of something that you do every day: standing at a lectern in a dusty room, for example, lecturing to a roomful of teen-agers above whom hang almost visible clouds of hormones; or running a seminar, hoping to find the question that will make people talk even though it’s spring and no one has done the reading; or sitting in a department meeting as your colleagues act out their various professional identities, the Russian historians spreading gloom, the Germanists accidentally taking Poland, the Asianists grumbling about Western ignorance and lack of civility, and the Americanists expressing surprise at the idea that the world has other continents.

Suddenly, you find yourself wondering, how you can possibly be doing this.