Description

8vo, coth no dj, , 274 pages. Valued today for its development of the third law of planetary motion, Harmonice mundi (1619) was intended by Kepler to expand on ancient efforts to discern a Creators plan for the planetary system--an arrangement thought to be based on harmonic relationships. Challenging critics who characterize Keplers theories of harmonic astronomy as mystical, Bruce Stephenson offers the first thorough technical analysis of the music the astronomer thought the heavens made, and the logic that led him to find musical patterns in his data. In so doing, Stephenson illuminates crucial aspects of Keplers intellectual development, particularly his ways of classifying and drawing inferences. Beginning with a survey of similar theories associating music with the cyclic motions of planets, from Plato to Boethius, the author highlights Ptolemys Harmonics, a source of inspiration for Keplers later work. Turning to Kepler himself, Stephenson gives an account of his polyhedral theory, which explains the number and sizes of the planetary orbits in terms of the five regular poly-hedral. He then examines in detail an early theory that relates the planets vel-ocities to a musical chord, and analyzes Keplers unpublished commentary on Ptolemys Harmonics. Devoting most of his attention to Book Five of Harmonice mundi, in which Kepler elaborated on the musical structure of the planetary system, Stephenson lays important groundwork for any further evaluation of Keplers scientific thought. ex-library with samps and labels. ow very good.