Johannes Kepler Quotes

“Why should we place Christ at the top and summit of the human race? Was he kinder, more forgiving, more self-sacrificing than Buddha? Was he wiser, did he meet death with more perfect calmness, than Socrates? Was he more patient, more charitable, than Epictetus? Was he a greater philosopher, a deeper thinker, than Epicurus? In what respect was he the superior of Zoroaster? Was he gentler than Lao-tsze, more universal than Confucius? Were his ideas of human rights and duties superior to those of Zeno? Did he express grander truths than Cicero? Was his mind subtler than Spinoza’s? Was his brain equal to Kepler’s or Newton’s? Was he grander in death – a sublimer martyr than Bruno? Was he in intelligence, in the force and beauty of expression, in breadth and scope of thought, in wealth of illustration, in aptness of comparison, in knowledge of the human brain and heart, of all passions, hopes and fears, the equal of Shakespeare, the greatest of the human race?”
― Robert G. Ingersoll, About The Holy Bible

“My dear Kepler, what would you say of the learned here, who, replete with the pertinacity of the asp, have steadfastly refused to cast a glance through the telescope? What shall we make of this? Shall we laugh, or shall we cry?”
― Galileo Galilei, Frammenti e lettere

“I esteem myself happy to have as great an ally as you in my search for truth. I will read your work ... all the more willingly because I have for many years been a partisan of the Copernican view because it reveals to me the causes of many natural phenomena that are entirely incomprehensible in the light of the generally accepted hypothesis. To refute the latter I have collected many proofs, but I do not publish them, because I am deterred by the fate of our teacher Copernicus who, although he had won immortal fame with a few, was ridiculed and condemned by countless people (for very great is the number of the stupid).

{Letter to fellow revolutionary astronomer Johannes Kepelr}”
― Galileo Galilei, Frammenti e lettere

“If the people of Europe had known as much of astronomy and geology when the bible was introduced among them, as they do now, there never could have been one believer in the doctrine of inspiration. If the writers of the various parts of the bible had known as much about the sciences as is now known by every intelligent man, the book never could have been written. It was produced by ignorance, and has been believed and defended by its author. It has lost power in the proportion that man has gained knowledge. A few years ago, this book was appealed to in the settlement of all scientific questions; but now, even the clergy confess that in such matters, it has ceased to speak with the voice of authority. For the establishment of facts, the word of man is now considered far better than the word of God. In the world of science, Jehovah was superseded by Copernicus, Galileo, and Kepler. All that God told Moses, admitting the entire account to be true, is dust and ashes compared to the discoveries of Descartes, Laplace, and Humboldt. In matters of fact, the bible has ceased to be regarded as a standard. Science has succeeded in breaking the chains of theology. A few years ago, Science endeavored to show that it was not inconsistent with the bible. The tables have been turned, and now, Religion is endeavoring to prove that the bible is not inconsistent with Science. The standard has been changed.”
― Robert G. Ingersoll, Some Mistakes of Moses

“Is it possible that the Pentateuch could not have been written by uninspired men? that the assistance of God was necessary to produce these books? Is it possible that Galilei ascertained the mechanical principles of 'Virtual Velocity,' the laws of falling bodies and of all motion; that Copernicus ascertained the true position of the earth and accounted for all celestial phenomena; that Kepler discovered his three laws—discoveries of such importance that the 8th of May, 1618, may be called the birth-day of modern science; that Newton gave to the world the Method of Fluxions, the Theory of Universal Gravitation, and the Decomposition of Light; that Euclid, Cavalieri, Descartes, and Leibniz, almost completed the science of mathematics; that all the discoveries in optics, hydrostatics, pneumatics and chemistry, the experiments, discoveries, and inventions of Galvani, Volta, Franklin and Morse, of Trevithick, Watt and Fulton and of all the pioneers of progress—that all this was accomplished by uninspired men, while the writer of the Pentateuch was directed and inspired by an infinite God? Is it possible that the codes of China, India, Egypt, Greece and Rome were made by man, and that the laws recorded in the Pentateuch were alone given by God? Is it possible that Æschylus and Shakespeare, Burns, and Beranger, Goethe and Schiller, and all the poets of the world, and all their wondrous tragedies and songs are but the work of men, while no intelligence except the infinite God could be the author of the Pentateuch? Is it possible that of all the books that crowd the libraries of the world, the books of science, fiction, history and song, that all save only one, have been produced by man? Is it possible that of all these, the bible only is the work of God?”
― Robert G. Ingersoll, Some Mistakes of Moses

“In the beginning of the year 1665 I found the Method of approximating series & the Rule for reducing any dignity of any Binomial into such a series. The same year in May I found the method of Tangents of Gregory & Slusius, & in November had the direct method of fluxions & the next year in January had the Theory of Colours & in May following I had entrance into ye inverse method of fluxions. And the same year I began to think of gravity extending to ye orb of the Moon & (having found out how to estimate the force with wch [a] globe revolving within a sphere presses the surface of the sphere) from Kepler's rule of the periodic times of the Planets being in sesquialterate proportion of their distances from the center of their Orbs, I deduced that the forces wch keep the Planets in their Orbs must [be] reciprocally as the squares of their distances from the centers about wch they revolve: & thereby compared the force requisite to keep the Moon in her Orb with the force of gravity at the surface of the earth, & found them answer pretty nearly. All this was in the two plague years of 1665-1666. For in those days I was in the prime of my age for invention & minded Mathematicks & Philosophy more then than at any time since.”
― Isaac Newton

“Kepler's laws, although not rigidly true, are sufficiently near to the truth to have led to the discovery of the law of attraction of the bodies of the solar system. The deviation from complete accuracy is due to the facts, that the planets are not of inappreciable mass, that, in consequence, they disturb each other's orbits about the Sun, and, by their action on the Sun itself, cause the periodic time of each to be shorter than if the Sun were a fixed body, in the subduplicate ratio of the mass of the Sun to the sum of the masses of the Sun and Planet; these errors are appreciable although very small, since the mass of the largest of the planets, Jupiter, is less than 1/1000th of the Sun's mass.”
― Isaac Newton, The Principia : Mathematical Principles of Natural Philosophy

“What a deep [trust] in the rationality of the structure of the world and what a longing to understand even a small glimpse of the reason revealed in the world there must have been in Kepler and Newton to enable them to unravel the mechanism of the heavens in long years of lonely work!”
― Albert Einstein

“It is to these two discoveries by Bradley that we owe the exactness of modern astronomy. .... This double service assures to their discoverer the most distinguished place (after Hipparchus and Kepler) above the greatest astronomers of all ages and all countries.”
― Jean-Baptiste Joseph Delambre

“Kepler’s discovery would not have been possible without the doctrine of conics. Now contemporaries of Kepler—such penetrating minds as Descartes and Pascal—were abandoning the study of geometry ... because they said it was so UTTERLY USELESS. There was the future of the human race almost trembling in the balance; for had not the geometry of conic sections already been worked out in large measure, and had their opinion that only sciences apparently useful ought to be pursued, the nineteenth century would have had none of those characters which distinguish it from the ancien régime.”
― Charles Sanders Peirce, Collected Papers of Charles Sanders Peirce, Volumes V and VI, Pragmatism and Pragmaticism and Scientific Metaphysics

“After a duration of a thousand years, the power of astrology broke down when, with Copernicus, Kepler, and Galileo, the progress of astronomy overthrew the false hypothesis upon which the entire structure rested, namely the geocentric system of the universe. The fact that the earth revolves in space intervened to upset the complicated play of planetary influences, and the silent stars, related to the unfathomable depths of the sky, no longer made their prophetic voices audible to mankind. Celestial mechanics and spectrum analysis finally robbed them of their mysterious prestige.”
― Franz Cumont, Astrology and Religion Among the Greeks and Romans

“Foreshadowings of the principles and even of the language of [the infinitesimal] calculus can be found in the writings of Napier, Kepler, Cavalieri, Fermat, Wallis, and Barrow. It was Newton's good luck to come at a time when everything was ripe for the discovery, and his ability enabled him to construct almost at once a complete calculus.”
― W.W. Rouse Ball, A Short Account of the History of Mathematics

“When Kepler suggested that the tides are due to attractive forces emanating from the moon, Galileo shrugged the idea off as 'occult fantasy' because it involved action-at-a-distance and thus contradicted the laws of nature.”
― Arthur Koestler, The Roots of Coincidence