Before taking leave of the “Principles of Sociology,” we should caution the reader against a misconception that might seem, at first sight, to find some warrant in the following remark of a sympathetic reviewer: “Like Aristotle, he [Mr. Spencer] has had to delegate large portions of his work to be done for him by others.” As our author has himself pointed out in “Facts and Comments,” the reviewer’s reference will be rightly interpreted by those who know that the work delegated by Aristotle to others was simply the collection of materials for his Natural History, not the classification of those materials, much less the drawing of inductions from them. As not one reader in ten knows this, however, wrong impressions are likely to be made by the reviewer’s remark. Mr. Spencer’s name being especially associated with the “Synthetic Philosophy,” the sentence quoted will suggest to many the thought that large portions of that work were written by deputy. This, of course, the reviewer did not mean to say. The work to which he referred is entitled “Descriptive Sociology, or groups of sociological facts, classified and arranged by Herbert Spencer, compiled and abstracted by David Duncan, Richard Scheppig and James Collier,” eight parts of which have thus far appeared. Knowing that he should be unable to read all the works of travel and history containing the facts he should need when dealing with the science of society, Mr. Spencer engaged these gentlemen—first one, then two, then three—to read up for him and arrange the extracts they made in a manner prescribed. With much material he had himself accumulated in the course of many years, our author incorporated a much larger amount of material derived from the compilations just mentioned when writing the “Principles of Sociology.”