I love reading history, and the shelves in my living room are lined with fat, fact-filled books. There’s “The Hemingses of Monticello,” about the family of Thomas Jefferson’s slave mistress; there’s “House of Cards,” about the fall of Bear Stearns; there’s “Titan,” about John D. Rockefeller Sr. The problem is, as much as I’ve enjoyed these books, I don’t really remember reading any of them. Certainly I know the main points. But didn’t I, after underlining all those interesting parts, retain anything else? It’s maddening and, sorry to say, not all that unusual for a brain at middle age: I don’t just forget whole books, but movies I just saw, breakfasts I just ate, and the names, oh, the names are awful. Who are you?