Kepler and the Universe: How One Man Revolutionized Astronomy,

David K.
Prometheus Books
, 2015. $24.00 (253 pp.). ISBN 978-1-63388-106-8 Buy at Amazon

For a major part of the 20th century, Max Caspar’s Kepler was considered the standard biography of Johannes Kepler. In part it was stitched together from the introductions to the many volumes of the Gesammelte Werke (Collected Works) edited by the Kepler Commission of the Bavarian Academy of Sciences. It was comprehensive, solid, and yes, stolid. Occasionally there were flights of brilliant prose, as when Caspar wrote concerning the Harmonice mundi (Harmony of the World), “So his Harmonice appears as a great cosmic vision… . It belongs to the most sublime, which has been thought and devised by the human intellect, locked in the material world and desiring to lift itself out of it. It is a grandiose fugue on the theme ‘world, soul, God’ with a maestro finale” (Abelard-Schuman, page 290). But in general it was not fun to read.

Then, in 1959, Hutchinson published Arthur Koestler’s The Sleepwalkers: A History of Man’s Changing Vision of the Universe. The book included a section called “The Watershed,” a master storyteller’s reworking of Caspar’s text that roused up considerable interest in Kepler. Of the variety of accounts that have followed in English, the best—and these are fun to read—are Kitty Ferguson’s Tycho and Kepler: The Unlikely Partnership That Forever Changed Our Understanding of the Universe (Walker Books, 2002), and the subject of this review, David Love’s Kepler and the Universe: How One Man Revolutionized Astronomy.

Love, who holds a degree in astronomy, gave up his career as an accountant to become a lecturer and writer in astronomy. He is obviously a fan of Kepler. His book is sprinkled with his own photographs of Keplerian sites throughout Europe. And when it comes to technical Kepleriana, he has produced the clearest mathematical outline that I’ve ever seen of Kepler’s major book, Astronomia nova (The New Astronomy).

Kepler’s professional accomplishments ranged far beyond the three planetary laws for which he is famous. His observations of the supernova of 1604 enabled 20th-century astronomers to find its remnant; his discussion of six-cornered snowflakes is seen as a pioneering treatise on crystallography; his book on optical theory analyzed the astronomical telescope; his discussion of wine measures is part of the prehistory of integral calculus; and he published one of the first tables of logarithms. Apart from the logarithms, it’s all here. The book has just a few slips: For example, the inventor of the telescope is Lipperhey, not Lippershey, and Kepler’s great book that includes his third planetary law should be abbreviated as Harmonice mundi, not Harmonices mundi and translated as Harmony of the World, not Harmonies of the World. But those mostly originate with other authors.

Love is more of an astronomy enthusiast than historian of science; perhaps that’s why he takes umbrage when Kepler gets carried away with supposing that the regular polyhedra could control the spacing of the planets. Of course it was part of Kepler’s genius to notice that something just as arbitrary “explained” the spacing of the planets in the Ptolemaic system. Namely, one could assume that the planetary spheres, with thickness defined by their epicycles, were nested in a way so as to fill all space. In the Copernican system the relative spacings were known, and it was Kepler’s brilliance to try to find a geometrical explanation, nutty as the explanation might appear to us today. Tycho Brahe had also thought about using regular polyhedra in some way, and hence the idea resonated with him when Kepler’s letter looking for a job arrived. Without his crazy idea, maybe Kepler would never have got access to Tycho’s fabulous observations of Mars!

Likewise Love is impatient with Kepler’s infatuation with astrology, and he gives it short shrift despite one of the volumes of the Gesammelte Werke being full of hundreds of Kepler’s horoscopes. It’s not really possible to explore Kepler’s unusual mind without including such exotica. One way to get a broad appreciation of Kepler’s genius is to read Love’s engaging biography, and then to look at Patrick J. Boner’s Kepler’s Cosmological Synthesis: Astrology, Mechanism, and the Soul (Brill, 2013).

Owen Gingerich is a professor emeritus of astronomy and history of science at the Harvard–Smithsonian Center for Astrophysics in Cambridge, Massachusetts. His article, “The great Martian catastrophe and how Kepler fixed it” appeared on page 50 of the September 2011 issue of Physics Today.