"The stars in the heavens sing a music, if only we had ears to hear." — Pythagoras
Musica Universalis
"Some thinkers suppose that the motion of bodies of that size must produce a noise, since on our earth the motion of bodies far inferior in size and in speed of movement has that effect. Also, when the sun and the moon, they say, and all the stars, so great in number and in size, are moving with so rapid a motion, how should they not produce a sound immensely great? Starting from this argument and from the observation that their speeds, as measured by their distances, are in the same ratios as musical concordances, they assert that the sound given forth by the circular movement of the stars is a harmony. Since, however, it appears unaccountable that we should not hear this music, they explain this by saying that the sound is in our ears from the very moment of birth and is thus indistinguishable from its contrary silence, since sound and silence are discriminated by mutual contrast. What happens to men, then, is just what happens to copper-smiths, who are so accustomed to the noise of the smithy that it makes no difference to them." - Aristotle
“The concept of the "music of the spheres" incorporates the metaphysical principle that mathematical relationships express qualities or "tones" of energy that manifests in numbers, visual angles, shapes and sounds — all connected within a pattern of proportion. Pythagoras first identified that the pitch of a musical note is an inverse proportion to the length of the string that produces it, and that intervals between harmonious sound frequencies form simple numerical ratios. Pythagoras proposed that the Sun, Moon and planets all emit their own unique hum based on their orbital revolution, and that the quality of life on Earth reflects the tenor of celestial sounds which are physically imperceptible to the human ear. Subsequently, Plato described astronomy and music as "twinned" studies of sensual recognition: astronomy for the eyes, music for the ears, and both requiring knowledge of numerical proportions.”
Boethius, in his influential work De Musica, described three categories of music:
Musica mundana (sometimes referred to as musica universalis).
Musica humana (the internal music of the human body).
Musica quae in quibusdam constituta est instrumentis (sounds made by singers and instrumentalists).
"The Sun, guardian of Jupiter," and the verses of David, "He placed his throne in the Sun," and "The Lord is the Sun," etc., said that he understood perfectly how the Pythagoreans could believe that all the globes disseminated through Space were rational Intelligences, facultates ratiocinativae, circulating around the Sun, "in which resides a pure Spirit of fire; the source of the general harmony." — De Motibus - Planetarum Harmonicis
Music of the Spheres
"For there is a musicke where-ever there is a harmony, order or proportion; and thus farre we may maintain the musick of the spheres; for those well ordered motions, and regular paces, though they give no sound unto the eare, yet to the understanding they strike a note most full of harmony."
— Johannes Kepler - Musica Universalis
“The Light did not scatter randomly, but flowed in sacred proportion, forming concentric circles of creation. These are the spheres of the heavens, harmonized by number, weight, and measure.” - Robert Fludd, (De Musica Mundana)
“God is the Architect of all harmony. Geometry is His design, music is His expression, and man is His instrument.” - Robert Fludd, (De Musica Mundana)
The Musician
The musician allows himself to be easily moved by beauty, and admires it greatly; but he is not able by himself to achieve the intuition of the beautiful. He needs the stimulation of external impressions. Just as some timorous being is awakened by the least noise, the musician is sensitive to the beauty of the voice and of harmonies. He avoids all that seems contrary to the laws of harmony and of unity, and enjoys rhythm and melodies in instrumental and vocal music. After these purely sensual intonations, rhythm and tunes, he will surely in them come to distinguish form from matter, and to contemplate the beauty existing in their proportions and relations. He will have to be taught that what excites his admiration in these things, is their intelligible harmony, the beauty it contains, and, in short, beauty absolute, and not particular. He will have to be introduced to philosophy by arguments that will lead him to recognize truths that he ignored, though he possessed them instinctively. Such arguments will be specified elsewhere." - Plotinus, First Ennead Book Three: Of Dialectic, or the Means of Raising the Soul to the Intelligible World (Guthrie translation)