“Nicholson Baker does not look like a dirty-book writer. … He wears round, owlish glassesÂ, and in early book-jacket photographs, when his beard was darker and more closely trimmed than it is now, he reminds you of one of those earnest Russian intellectuals of the 19th century. Nowadays, with the beard grown out and nearly white, he could easily get seasonal work as a shopping-mall Santa.”