Therefore, if it be the aim of any person to practise music with skill and judgment, let him imitate the ancient manner ; let him also adorn it with those other sciences, and make philosophy his tutor, which is sufficient to judge what is in music decent and useful. For music being generally divided into three parts, diatonic, chromatic, and enharmonie, it behooves one who comes to learn music to understand poetry, which uses these three parts, and to know how to express his poetical inventions in proper musical form. First therefore we are to consider that all musical learning is a sort of habituation, which does not teach the reason of her precepts at one and the same time to the learner. Moreover, we are to understand that to such an education there is not requisite an enumeration of its several divisions, but every one learns by chance what either the master or scholar, according to the authority of the one and the liberty of the other, has most affection for. But the more prudent sort reject this chance-medley way of learning, as the Lacedaemonians of old, the Mantineans, and Pallenians, who, making choice either of one single method or else but very few styles, used only that sort of music which they deemed most proper to regulate the inclinations of youths.