In this day the subject-matter of thought and belief has so increased upon us, that a far higher mental formation is required than was necessary in times past, and higher than we have actually reached. The whole world is brought to our doors every morning, and our judgment is required upon social concerns, books, persons, parties, creeds, national acts, political principles and measures. We have to form our opinion, make our profession, take our side on a hundred matters on which we have but little right to speak at all. But we do speak, and must speak, upon them, though neither we nor those who hear us are well able to determine what is the real position of our intellect relatively to those many questions, one by one, on which we commit ourselves; and then, since many of these questions change their complexion with the passing hour, and many require elaborate consideration, and many are simply beyond us, it is not wonderful, if, at the end of a few years, we have to revise or to repudiate our conclusions; and then we shall be unfairly said to have changed our certitudes, and shall confirm the doctrine, that, except in abstract truth, no judgment rises higher than probability. Such are the mistakes about certitude among educated men; and after referring to them, it is scarcely worth while to dwell upon the absurdities and excesses of the rude intellect, as seen in the world at large; as if any one could dream of treating as deliberate assents, as assents upon assents, as convictions or certitudes, the prejudices, credulities, infatuations, superstitions, fanaticisms, the whims and fancies, the sudden irrevocable plunges into the unknown, the obstinate determinations,—the offspring, as they are, of ignorance, wilfulness, cupidity, and pride,—which go so far to make up the history of mankind; yet these are often set down as instances of certitude and of its failure. 4.