Musical consonance occurs in the element which is the mean of all (i.e. air), and reaches the ears through motion, spherical motion: so that it is not surprising that it should be fitting to the soul, which is both the mean of things, and the origin of circular motion. In addition, musical sound, more than anything else perceived by the senses, conveys, as if animated, the emotions and thoughts of the singer's or player's soul to the listeners' souls; thus it preeminently corresponds with the soul. Moreover, as regards sight, although visual impressions are in a way pure, yet they lack the effectiveness of motion, and are usually perceived only as an image, without reality; normally therefore, they move the soul only slightly. Smell, taste, and touch are entirely material, and rather titillate the sense-organs than penetrate the depths of the soul. But musical sound by the movement of the air moves the body: by purified air it excites the aerial spirit which is the bond of body and soul: by emotion it affects the senses, and at the same time the soul: by meaning it works on the mind: finally, by the very movement of the subtle air it penetrates strongly: by its contemperation it flows smoothly: by the convormity of its quality it floods us with a wonderful pleasure: by its nature, both spiritual and material, it at once seizes, and claims as its own, man in his entirety.


--Marsilio Ficino