First of all, I should ask, what precisely is meant by "the Greeks"? The argument is founded partly on the number of great thinkers, poets, and artists, in proportion to the population. Now, it is obviously essential to a scientific statement that we should know what is the population indicated. If we compare the number of great men at Athens in its best period with the number of free Athenians, we shall get one ratio; if we admit the Athenian slaves, or add Boeotia and other Greek States to our population, we get quite a different ratio. And the difference is of immense importance. The smaller the population, the higher the excellence indicated by a given number of great men; but, also, the smaller the population, the less is the wonder that it should have died out or been swallowed up in the whirlpools of political, religious, and social convulsions. A similar remark applies in regard to the period during which this race flourished. When did they begin and when did they cease to be superior to other people? Till the statement is more precise we do not even know what are the phenomena to be explained; and the case is susceptible of any number of explanations. Did the superior race cease to be prolific; or was it prolific, but of inferior descendants; and, if so, was it because it was mixed with races of an inferior stamp; or was it because its position exposed it to the attacks of more numerous enemies; or because its energy led it to attempt impossible feats? Has it died out, or has it been swamped by other races? To answer such questions is absolutely necessary before we can say positively that the higher organisation was the cause of the decay, or that it did not cause the decay by some indirect process due to the special combination of circumstances. But to answer such questions, if they be answerable at all, would require the investigations of a lifetime, and a mastery of a whole series of studies, historical, statistical, ethnological, and so forth, in which I am an absolute ignoramus. But I cannot perceive that Mr. Kidd claims more than second-hand information.