Institutio Oratoria

Consequently in my opinion artistic structure gives force and direction to our thoughts just as the throwing-thong and the bowstring do to the spear and the arrow. And for this reason all the best scholars are convinced that the study of structure is of the utmost value, not merely for charming the ear, but for stirring the soul.

For in the first place nothing can penetrate to the emotions that stumbles at the portals of the ear, and secondly man is naturally attracted by harmonious sounds. Otherwise it would not be the case that musical instruments, in spite of the fact that their sounds are inarticulate, still succeed in exciting a variety of different emotions in the hearer.