The music or harmony of the spheres. Pythagoras, having
ascertained that the pitch of notes depends on the rapidity of
vibrations, and also that the planets move at different rates of
motion, concluded that the sounds made by their motion must vary
according to their different rates of motion. As all things in nature
are harmoniously made, the different sounds must harmonise, and the
combination he called the “harmony of the spheres.” Kepler has a
treatise on the subject.
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