Note three things. (1) The spiritual life of Rome during these 800 years has its origin in imported foreign movements. The source of the ethical movement is Greek, that of the religious movement is Oriental. (2) The two movements overlap. Indeed, each from its beginning to its end covers about 600 years. More precisely the ethical movement did not disappear until about 200 A. D.; the religious movement began about 200 B. C. Ethical considerations dominate the first and religious impulses the second period. (3) The century and a half from 150 B. C. to 1 A. D. is a period of transition. It is the time when the emphasis changes from ethics to religion. It is a period of unsettled conditions both politically and intellectually. Politically it is the time of the Civil wars and the formation of the empire. Intellectually it is the time of Eclecticism and Skepticism. =The Undercurrent of Skepticism in the Hellenic-Roman Period.= If we go beneath the surface of the chronological divisions of this period, which have been given above, we shall find their significance in the undercurrent of Skepticism, which runs from the beginning to the end of the period, and includes both its ethical and religious phases. “Skepticism” is a word with a history of its own, but, as philosophically used, it means the disbelief in the possibility of true knowledge. Skepticism was the fundamental frame of mind that gradually grew to conscious expression in the entire ancient world, although it was entirely at variance with the spirit of the Greek culture that had been superimposed upon that world. As an undercurrent――a widespread feeling――Skepticism pervaded the whole period, while at different times and places it appeared distinctly on the surface. These were 800 years of lack of confidence in the power of the human reason, but the really negative character of the time is often concealed by dogmatic teachings of the philosophical Schools. Dogmatic Skepticism does not appear except with reference to the positive teachings of the Schools, and then it appears conspicuously. The successive stages of Skepticism can have their clear outline, therefore, only after the positive philosophical teachings, contemporary with it and opposed by it, have been understood. This is the reason for treating the Skeptics after and not before the Schools. The reader will, however, lose the whole meaning of the Hellenic-Roman Period if he does not see that it is fundamentally Skeptical; that in the Ethical Division the Schools furnished the occasion of its appearance, and that in the Religious Division religious faith rose because Skepticism had taken possession of the field of knowledge. The ethical Schools stood as the last representatives of the old Greek rationalism of the Systematic Period, but even they yielded to the Skeptical spirit of the time. Stoicism, Epicureanism, and Skepticism seek the same end,――the withdrawal of the