“Music is then the knowledge of that which relates to love in harmony and system. In the very system of harmony and rhythm, it is easy to distinguish love. The double love is not distinguishable in music itself; but it is required to apply it to the service of mankind by system and harmony, which is called poetry, or the composition of melody; or by the correct use of songs and measures already composed, which is called discipline; then one can be distinguished from the other, by the aid of an extremely skilful artist. And the better love ought to be honoured and preserved for the sake of those who are virtuous, and that the nature of the vicious may be changed through the inspiration of its spirit. This is that beautiful Uranian love, the attendant on the Uranian muse: the Pandemian is the attendant of Polyhymnia; to whose influence we should only so far subject ourselves, as to derive pleasure from it without indulging to excess; in the same manner as, according to our art, we are instructed to seek the pleasures of the table, only so far as we can enjoy them without the consequences of disease. In music, therefore, and in medicine, and in all other things, human and divine, this double love ought to be traced and discriminated; for it is in all things. “Even the constitution of the seasons of the year is penetrated with these contending principles. For so often as heat and cold, dryness and moisture, of which I spoke before, are influenced by the more benignant love, and are harmoniously and temperately intermingled with the seasons, they bring maturity and health to men, and to all the other animals and plants. But when the evil and injurious love assumes the dominion of the seasons of the year, destruction is spread widely abroad. Then pestilence is accustomed to arise, and many other blights and diseases fall upon animals and plants: and hoar frosts, and hails, and mildew on the corn, are produced from that excessive and disorderly love, with which each season of the year is impelled towards the other; the motions of which and the knowledge of the stars, is called astronomy. All sacrifices, and all those things in which divination is concerned (for these things are the links by which is maintained an intercourse and communion between the Gods and men), are nothing else than the science of preservation and right government of Love. For impiety is accustomed to spring up, so soon as any one ceases to serve the more honourable Love, and worship him by the sacrifice of good actions; but submits himself to the influences of the other, in relation to his duties towards his parents, and the Gods, and the living, and the dead. It is the object of divination to distinguish and remedy the effects of these opposite loves; and divination is therefore the author of the friendship of Gods and men, because it affords the knowledge of what in matters of love is lawful or unlawful to men.