Among my critics there are not a few to whom I feel deeply indebted for the careful attention which they have given to the exposition thus hampered; and further weakened, I am afraid, by my forgetfulness of a maxim touching lectures of a popular character, which has descended to me from that prince of lecturers, Mr. Faraday. He was once asked by a beginner, called upon to address a highly select and cultivated audience, what he might suppose his hearers to know already. Whereupon the past master of the art of exposition emphatically replied "Nothing!" To my shame as a retired veteran, who has all his life profited by this great precept of lecturing strategy, I forgot all about it just when it would have been most useful. I was fatuous enough to imagine that a number of propositions, which I thought established, and which, in fact, I had advanced without challenge on former occasions, needed no repetition. I have endeavoured to repair my error by prefacing the lecture with some matter--chiefly elementary or recapitulatory--to which I have given the title of "Prolegomena" I wish I could have hit upon a heading of less pedantic aspect which would have served my purpose; and if it be urged that the new building looks over large for the edifice to which it is added, I can only plead the precedent of the ancient architects, who always made the adytum the smallest part of the temple. If I had attempted to reply in full to the criticisms to which I have referred, I know not what extent of ground would have been covered by my pronaos. All I have endeavoured to do, at present, is to remove that which seems to have proved a stumbling-block to many--namely, the apparent paradox that ethical nature, while born of cosmic nature, is necessarily at enmity with its parent. Unless the arguments set forth in the Prolegomena, in the simplest language at my command, have some flaw which I am unable to discern, this seeming paradox is a truth, as great as it is plain, the recognition of which is fundamental for the ethical philosopher. We cannot do without our inheritance from the forefathers who were the puppets of the cosmic process; the society which renounces it must be destroyed from without. Still less can we de with too much of it; the society in which it dominates must be destroyed from within. The motive of the drama of human life is the necessity, laid upon every man who comes into the world, of discovering the mean between self-assertion and self-restraint suited to his character and his circumstances. And the eternally tragic aspect of the drama lies in this: that the problem set before us is one the elements of which can be but imperfectly known, and of which even an approximately right solution rarely presents itself, until that stern critic, aged experience, has been furnished with ample justification for venting his sarcastic humour upon the irreparable blunders we have already made.