I. (A. R.) Why is A like B? (answerable): as, Why is a gentleman who gives a young lady a young dog, like a person who rides rapidly up hill? A. Because he gives a gallop up (gal-a-pup). _Sub-variety_; depending upon a violation of something like the “principle of excluded middle,” a very fallacy of a fallacy; such as the ancient “nigger-minstrel!” case, Why is an elephant like a brick? A. Because neither of them can climb a tree. II. (A. D.) Why is A _unlike_ B? (answerable) usually put thus: What is the difference between A and B? (Figure I., if worded in the same style, would become: What is the similarity between A and B?): as, What is the difference between the old United-States Bank and the Fulton Ferry-boat signals in thick weather? A. One is a fog whistle, and the other is a Whig fossil. III. (U. R.) Why is A like B? (unanswerable): as Charles Lamb’s well-known question, Is that your own hare, or a wig? IV. (U. D.) Why is A _unlike_ B? (unanswerable): i. e., What is the difference, &c, as, What is the difference between a fac simile and a sick family; or between hydraulics and raw-hide licks? But let me not diverge too far into frivolity. All the hopefully difficult questions Dr. Hicok set down and classified. He compiled a set of rules on the subject, and indeed developed a whole philosophy of it, by which he struck off, as soluble, questions or classes of them. Some he thought out himself; others were now and then answered in some learned book, that led the way through the very heart of one or another of his biggest mill-stones. So it was really none too much time that he had; and, in truth, he did not actually decide upon his three questions, until just a week before the fearful day when he was to put them. It came at last, as every day of reckoning surely comes; and Dr. Hicok, memorandum in hand, sat in his comfortable library about three o’clock on one beautiful warm summer afternoon, as pale as a sheet, his heart thumping away like Mr. Krupp’s biggest steam-hammer at Essen, his mouth and tongue parched and feverish, a pitcher of cold water at hand from which he sipped and sipped, though it seemed as if his throat repelled it into “the globular state,” or dispersed it into steam, as red-hot iron does. Around him were the records of the vast army of doubters and quibblers in whose works he had been hunting, as a traveller labours through a jungle, for the deepest doubts, the most remote inquiries.