A preface rather induces a man to speak of himself, which is deemed the worst subject upon which he can speak. In history we become acquainted with things, but in a preface with the author; and, for a man to treat of himself, may be the most difficult talk of the two: for in history, facts are produced ready to the hand of the historian, which give birth to thought, and it is easy to cloath that thought in words. But in a preface, an author is obliged to forge from the brain, where he is sometimes known to forge without fire. In one, he only reduces a substance into form; but in the other, he must create that substance.