Kepler was a brilliant thinker and a lucid writer, but he was a disaster as a classroom teacher. He mumbled. He digressed. He was at times utterly incomprehensible. He drew only a handful of students his first year at Graz; the next year there were none - Carl Sagan
A law explains a set of observations; a theory explains a set of laws. The quintessential illustration of this jump in level is the way in which Newton's theory of mechanics explained Kepler's law of planetary motion - John L Casti
It is important that in Kepler’s view the anima terrae is responsible for the weather and also for meteoric phenomena. Too much rain, for instance, is an illness of the earth - Wolfgang Pauli
Among the great men who have philosophized about the tides, the one who surprised me most is Kepler. He was a person of independent genius - Galileo Galilei
One wonders how many modern scientists faced by a similar situation in their work would fail to be impressed by such remarkable numerical coincidences - Fred Hoyle
Kepler was visited by a revelation that was to alter radically the future of astronomy - Carl Sagan
Kepler became interested in the action of the moon on the water, and in other occult phenomena, and similar childishness - Galileo Galilei
One of the first modern astronomers and last scientific astrologers - Carl Sagan
Fiercely competitive and prone to a certain amount of quarrelsomeness and violence - Albert Koestler
The first astrophysicist and the last scientific astrologer - Carl Sagan
the astrologer who killed astrology - Owen Gingerich