Where is Prague?

Cosmic Mystery or the Hand of God, Geometer

Johannes Kepler stood at a cusp in history; the last scientific astrologer was the first astrophysicist of the Earth.

In 1598, one of the many premonitory tremors of the coming Thirty Years’ War engulfed Kepler, a provincial schoolteacher of humble origins, absolutely unknown to all but a few scientists. He was living in Graz, a cozy German town, when the war began. Fortunately for Kepler, Tycho Brahe, a famous astronomer offered the mathematician to join him in Prague.

Leaving Graz, Kepler, his wife and stepdaughter set out on the difficult journey to Prague.

Chronically ill, having lost two young children, his wife was described as “ignorant”. She had no understanding of her husband’s work and, having been raised among the minor rural gentry, she despised his impecunious profession. She didn’t know where Prague was and what country was it the capital of.

Kepler for his part described his thoughts toward his wife as follows: "for my studies sometimes made me thoughtless; but I learned my lesson, I learned to have patience with her. When I saw that she took my words to heart, I would rather have bitten by own finger to give her further offense”.

But Kepler aspired to become a colleague of the great Tycho Brahe, who for thirty-five years had devoted himself to the measurement of a clockwork universe, ordered and precise.

Kepler’s expectations were to be unfulfilled. Tycho himself was a flamboyant figure, festooned with a golden nose, the original having been lost in a student duel.

“Hypocrisy I have never learned. I am in earnest about faith. I do not play with it”, Kepler said and he tried to work harder and harder in order to forget that his wife didn’t know where they lived.

Kepler’s fundamental innovation is nothing short of breathtaking: he proposed that quantitative physical laws that apply to the Earth are also the underpinnings of quantitative physical laws that govern the heavens. It was the first non-mystical explanation of motion in the heavens. This discovery made the Earth a province of the Cosmos.

“Astronomy”, Kepler said, “is part of physics”. He considered that his first aim was to show that “the celestial machine is to be likened not to a divine organism but rather to a clockwork…, insofar as nearly all the manifold movements are carried out by means of a single, quite simple magnetic force, as in the case of clockwork, where all motions are caused by a simple weight.”

There were only six planets known in Kepler’s time : Mercury, Venus, Earth,  Mars, Jupiter and Saturn. Kepler wondered, why only six? Why not twenty or a hundred? Why did they have the spacing between their orbits that Copernicus had deduced? No one has ever asked such questions before. There were known five regular or “platonic” solids, whose sides where regular polygons, as known to the ancient Greek mathematicians after their time of Pythagoras.

Curiously enough, within the symphony of voices, Kepler believed that the speed of each planet correspond to certain notes in the Latinate musical scale popular in his day – do, re, mi, fa, sol, la, ti, do. He claimed that in the harmony of the spheres, the tones of Earth are fa and mi, that the Earth is forever humming fa and mi, and that they stand in a straightforward way for the Latin word for famine.

Kepler believed he had recognised the invisible supporting structures for the spheres of the six planets. He called his revelation the Cosmic Mystery and thought that connection between the solids of Pythagoras and the disposition of the planets could admit but one explanation: The Hand of God, Geometer.

One week after Kepler’s discovery of his third law of nature, the incident that unleashed the Thirty Years’ War transpired in Prague. The war’s convulsions shattered the lives of millions, Kepler among them. He lost his wife and son to an epidemic carried by the soldiery, his royal patron was deposed, and he was excommunicated by the Lutheran Church for his uncompromising individualism on matters of doctrine. Johannes Kepler was a refugee once again. He had envisioned Tycho’s domain as a refuge from the evils of the time, as the place where his Cosmic Mystery would be confirmed, but he had to flee Prague, a town whose whereabouts his wife ignored.

mosaic carré

The Hand of God, Geometer, revealed the Cosmic Mystery and created a Holy Geometry. Image by ©
Megan Jorgensen

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