Years ago, I was looking through a box of artifacts from the life of Henry Hazlitt (1894–1993) and came across some of his old Big Chief tablets, the sort that people once used in elementary school. The handwriting was youthful, perhaps that of a fifth grader, and the pencil marks thick, as if from a child's writing tool.

So I was astonished to find, in young Henry's hand, extensive notes on Baruch Spinoza's treatise on ethics. And that was only the beginning. There were piles of these tablets, with notes on William Shakespeare, Adam Smith, David Hume, Herbert Spencer, Thomas Paine, Charles Darwin, Sigmund Freud, Ralph Waldo Emerson, and other great thinkers.