Johannes Kepler was a German astronomer, mathematician, and astrologer.

Johannes Kepler is a key figure in the 17th-century scientific revolution, best known for his laws of planetary motion, and his books Astronomia nova, Harmonices Mundi, and Epitome Astronomiae Copernicanae.

Kepler was born on December 27, the feast day of St John the Evangelist, 1571, in the Free Imperial City of Weil der Stadt.

He was introduced to astronomy at an early age and developed a love for it that would span his entire life.

Kepler was a mathematics teacher at a seminary school in Graz, later he became an assistant to the astronomer Tycho Brahe in Prague.

Johannes  Kepler lived in an era when there was no clear distinction between astronomy and astrology, but there was a strong division between astronomy and physics.

Kepler also incorporated religious arguments and reasoning into his work, motivated by the religious conviction and belief that God had created the world according to an intelligible plan that is accessible through the natural light of reason.

Kepler described his new astronomy as “celestial physics“, as “an excursion into Aristotle’s Metaphysics“, and as “a supplement to Aristotle’s On the Heavens“, transforming the ancient tradition of physical cosmology by treating astronomy as part of a universal mathematical physics.

Johannes  Kepler Quotes:

1. “Geometry has two great treasures; one is the Theorem of Pythagoras; the other, the division of a line into extreme and mean ratio. The first we may compare to a measure of gold; the second we may name a precious jewel.”

2. “I used to measure the skies, now I measure the shadows of Earth. Although my mind was sky-bound, the shadow of my body lies here.”

3. “Nature uses as little as possible of anything.”

4. “The soul of the newly born baby is marked for life by the pattern of the stars at the moment it comes into the world, unconsciously remembers it, and remains sensitive to the return of configurations of a similar kind.”

5. “The Earth is round, and is inhabited on all sides, is insignificantly small, and is borne through the stars.”

6. “before the origin of things, geometry was coeternal with the Divine Mind”

7. “The harnessing to a rational pursuit of the immense psychic energies derived from an irrational obsession seems to be another secret of genius, at least of genius of a certain type.”

8. “If my false figures came near to the facts, this happened merely by chance….These comments are not worth printing. Yet it gives me pleasure to remember how many detours I had to make, along how many walls I had to grope in the darkness of my ignorance until I found the door which lets in the light of truth….In such manner did I dream of the truth.”

9. “We do not ask for what useful purpose the birds do sing, for song is their pleasure since they were created for singing. Similarly, we ought not to ask why the human mind troubles to fathom the secrets of the heavens. The diversity of the phenomena of nature is so great, and the treasures hidden in the skies so rich, precisely in order that the human mind shall never be lacking in fresh nourishment.”

10. “Sky-bound was the mind, Earth-bound the body rests”

11. “When ships to sail the void between the stars have been built, there will step forth men to sail these ships.”

12. “Now because 18 months ago the first dawn, 3 months ago broad daylight but a very few days ago the full sun of the most highly remarkable spectacle has risen — nothing holds me back.”