An imagined gathering
1618 · Prague, Bohemia
Kepler celebrates the completion of his harmonies with Galileo and Bacon, and defends the music he hears in the planets.
Kepler has finished Harmonices mundi and invites Galileo and Bacon to a table in Prague to mark it. He is delighted with his discovery that the planets' speeds can be written as musical ratios, and he cannot resist explaining it to guests who are, in different ways, sceptical.
Galileo asks for the observations that prove it and Bacon asks what use it serves, and Kepler answers both with diagrams drawn on the cloth. The argument is warm rather than bitter, and it lasts through a capon, a frumenty, and a custard tart. By the end, even Bacon concedes that a hypothesis which fits the data is worth something, though he will not concede that it is knowledge.
Host: Johannes Kepler
Galileo Galilei — Kepler's correspondent and the most formidable observer of the age.
Francis Bacon — Philosopher and statesman, then at work on his programme for natural history.
First course
a period dish
Dessert
a period dish
Johannes Kepler
Kepler's three rules: elliptical orbits, equal areas swept in equal times, and the harmony between a planet's period and its distance.
Galileo Galilei
What Galileo saw through his improved spyglass — lunar mountains, Jupiter's moons, the phases of Venus — and why it unsettled the received cosmos.
Francis Bacon
Bacon's insistence that knowledge be gathered from experiment and observation, not deduced from ancient authority.
This gathering is an editorial recreation grounded in the biographies of those present; it did not necessarily take place as described.