It has been said that Religion is the great discoverer of truth, while Science follows her slowly and after a long interval. Heredity, so much discussed just now, is sometimes treated as if its principles were a great discovery of the present century. Popular science is apt to ignore history and to mistake a fresh nomenclature for an entirely new system of truth, and yet the immense and far-reaching importance of heredity has been one of the commonplaces of thought ever since history began. Science has been anticipated, not merely by religious feeling, but by a universal instinct. In the old world political and social systems have been based upon the recognition of the principle of heredity, and religion has sanctioned such recognition. Caste in India is a religious even more than a social institution; and we use the term figuratively in reference to ancient and modern life, even when the institution has not formally existed. Without the aid of definite civil or religious law the force of sentiment and circumstances suffices to establish an informal system of caste. Thus the feudal aristocracy and guilds of the Middle Ages were not without their rough counterparts in the Old Testament. Moreover, the local divisions of the Hebrew kingdoms corresponded in theory, at any rate, to blood relationships; and the tribe, the clan, and the family had even more fixity and importance than now belong to the parish or the municipality. A man’s family history or genealogy was the ruling factor in determining his home, his occupation, and his social position. In the chronicler’s time this was especially the case with the official ministers of religion, the Temple establishment to which he himself belonged. The priests, the Levites, the singers, and doorkeepers formed castes in the strict sense of the word. A man’s birth definitely assigned him to one of these classes, to which none but the members of certain families could belong.