“But although the attractive virtue of the earth extends upwards, as has been said, so very far, yet if any stone should be at a distance great enough to become sensible compared with the earth’s diameter, it is true that on the motion of the earth such a stone would not follow altogether; its own force of resistance would be combined with the attractive force of the earth, and thus it would extricate itself in some degree from the motion of the earth.”

— Johannes Kepler , book Astronomia nova

As quoted by Bryant, ibid.
Astronomia nova (1609)

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Johannes Kepler 51

German mathematician, astronomer and astrologer 1571–1630

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“If the attractive virtue of the moon extends as far as the earth, it follows with greater reason that the attractive virtue of the earth extends as far as the moon and much farther; and, in short, nothing which consists of earthly substance anyhow constituted although thrown up to any height, can ever escape the powerful operation of this attractive virtue.”

Johannes Kepler book Astronomia nova

As quoted by Bryant, ibid.
Astronomia nova (1609)

“Gravity is a mutual affection between cognate bodies towards union or conjunction (similar in kind to the magnetic virtue), so that the earth attracts a stone much rather than the stone seeks the earth.”

Johannes Kepler book Astronomia nova

As quoted by Bryant, ibid., pp. 35–36
Astronomia nova (1609)

“If we suppose the distance of the fixed stars from the sun to be so great that the diameter of the earth's orbit viewed from them would not subtend a sensible angle, or which amounts to the same, that their annual parallax is quite insensible; it will then follow that a line drawn from the earth in any part of its orbit to a fixed star, will always, as to sense, make the same angle with the plane of the ecliptic, and the place of the star, as seen from the earth, would be the same as seen from the sun placed in the focus of the ellipsis described by the earth in its annual revolution, which place may therefore be called its true or real place.
But if we further suppose that the velocity of the earth in its orbit bears any sensible proportion to the velocity with which light is propagated, it will thence follow that the fixed stars (though removed too far off to be subject to a parallax on account of distance) will nevertheless be liable to an aberration, or a kind of parallax, on account of the relative velocity between light and the earth in its annual motion.
For if we conceive, as before, the true place of any star to be that in which it would appear viewed from the sun, the visible place to a spectator moving along with the earth, will be always different from its true, the star perpetually appearing out of its true place more or less, according as the velocity of the earth in its orbit is greater or less; so that when the earth is in its perihelion, the star will appear farthest distant from its true place, and nearest to it when the earth is in its aphelion; and the apparent distance in the former case will be to that in the latter in the reciprocal proportion of the distances of the earth in its perihelion and its aphelion. When the earth is in any other part of its orbit, its velocity being always in the reciprocal proportion of the perpendicular let fall from the sun to the tangent of the ellipse at that point where the earth is, or in the direct proportion of the perpendicular let fall upon the same tangent from the other focus, it thence follows that the apparent distance of a star from its true place, will be always as the perpendicular let fall from the upper focus upon the tangent of the ellipse. And hence it will be found likewise, that (supposing a plane passing through the star parallel to the earth's orbit) the locus or visible place of the star on that plane will always be in the circumference of a circle, its true place being in that diameter of it which is parallel to the shorter axis of the earth's orbit, in a point that divides that diameter into two parts, bearing the same proportion to each other, as the greatest and least distances of the earth from the sun.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

Miscellaneous Works and Correspondence (1832), Demonstration of the Rules relating to the Apparent Motion of the Fixed Stars upon account of the Motion of Light.

“If the earth should cease to attract its waters to itself all the waters of the sea would be raised and would flow to the body of the moon.”

Johannes Kepler book Astronomia nova

As quoted by Bryant, ibid.
Astronomia nova (1609)

“If… the motion of the earth were circular, it would be violent and contrary to nature, and could not be eternal, since … nothing violent is eternal …. It follows, therefore, that the earth is not moved with a circular motion.”

Thomas Aquinas (1225–1274) Italian Dominican scholastic philosopher of the Roman Catholic Church

Commentaria in libros Aristotelis de caelo et mundo

“Nothing which consists of corporeal matter is absolutely light, but that is comparatively lighter which is rarer, either by its own nature, or by accidental heat. And it is not to be thought that light bodies are escaping to the surface of the universe while they are carried upwards, or that they are not attracted by the earth. They are attracted, but in a less degree, and so are driven outwards by the heavy bodies; which being done, they stop, and are kept by the earth in their own place.”

Johannes Kepler book Mysterium Cosmographicum

As translated and quoted by Bryant, ibid.
Mysterium Cosmographicum (1596), Astronomia nova (1609)

“We are now in a position to prove the following propositions : —
1. The distance of the sun from the earth is greater than eighteen times, but less than twenty times, the distance of the moon (from the earth); this follows from the hypothesis about the halved moon.
2. The diameter of the sun has the same ratio (as aforesaid) to the diameter of the moon.
3. The diameter of the sun has to the diameter of the earth a ratio greater than that which 19 has to 3, but less than that which 43 has to 6; this follows from the ratio thus discovered between the distances, the hypothesis about the shadow, and the hypothesis that the moon subtends one fifteenth part of a sign of the zodiac.”

Aristarchus of Samos ancient Greek astronomer and mathematician

p, 125
On the Sizes and Distances of the Sun and the Moon (c. 250 BC)

“If the moon and earth were not retained in their orbits by their animal force or some other equivalent, the earth would mount to the moon by a fifty-fourth part of their distance, and the moon fall towards the earth through the other fifty-three parts, and they would there meet, assuming, however, that the substance of both is of the same density.”

Johannes Kepler book Astronomia nova

As quoted by Bryant, ibid.
Astronomia nova (1609)

“[I]n the system of Copernicus there are found many and great inconveniences; for both the loading of the earth with triple motion is very incommodious, and the separation of the sun from the company of the planets, with which it has so many passions in common, is likewise a difficulty, and the introduction of so much immobility into nature, by representing the sun and stars as immovable, especially being of all bodies the highest and most radiant, and making the moon revolve about the earth in an epicycle, and some other assumptions of his, are the speculations of one who cares not what fictions he introduces into nature, provided his calculations answer. But if it be granted that the earth moves, it would seem more natural to suppose that there is no system at all, but scattered globes… than to constitute a system of which the sun is the centre. And this the consent of ages and of antiquity has rather embraced and approved. For the opinion concerning the motion of the earth is not new, but revived from the ancients… whereas the opinion that the sun is the centre of the world and immovable is altogether new… and was first introduced by Copernicus. …But if the earth moves, the stars may either be stationary, as Copernicus thought or, as it is far more probable, and has been suggested by Gilbert, they may revolve each round its own centre in its own place, without any motion of its centre, as the earth itself does… But either way, there is no reason why there should not be stars above stars til they go beyond our sight.”

Francis Bacon (1561–1626) English philosopher, statesman, scientist, jurist, and author

Descriptio Globi Intellectualis (1653, written ca. 1612) Ch. 6, as quoted in "Description of the Intellectual Globe," The Works of Francis Bacon (1889) pp. 517-518, https://books.google.com/books?id=lsILAAAAIAAJ&pg=PA517 Vol. 4, ed. James Spedding, Robert Leslie Ellis, Douglas Denon Heath.

“Thus, supposing these motions which I attribute to the earth”

Nicolaus Copernicus book De revolutionibus orbium coelestium

Preface Letter to Pope Paul III as quoted by Edwin Arthur Burtt in The Metaphysical Foundations of Modern Physical Science (1925)
De revolutionibus orbium coelestium (1543)
Context: When, therefore, I had long considered this uncertainty of traditional mathematics, it began to weary me that no more definite explanation of the movement of the world-machine established in our behalf by the best and most systematic builder of all, existed among the philosophers who had studied so exactly in other respects the minutest details in regard to the sphere. Wherefore I took upon myself the task of re-reading the books of all the philosophers which I could obtain, to seek out whether any one had ever conjectured that the motions of the spheres of the universe were other than they supposed who taught mathematics in the schools. And I found first, that, according to Cicero, Nicetas [assumed by modern editors to mean Hicetas] had thought the earth was moved. Then later I discovered, according to Plutarch, that certain others had held the same opinion.... When from this, therefore, I had conceived its possibility, I myself also began to meditate upon the mobility of the earth. And although the opinion seemed absurd, yet because I knew the liberty had been accorded to others before me of imagining whatsoever circles they pleased to explain the phenomena of the stars, I thought I also might readily be allowed to experiment whether, by supposing the earth to have some motion, stronger demonstrations than those of the others could be found as to the revolution of the celestial sphere. Thus, supposing these motions which I attribute to the earth later on in this book, I found at length by much and long observation, that if the motions of the other planets were added to the rotation of the earth and calculated as for the revolution of that planet, not only the phenomena of the others followed from this, but also it so bound together both the order and magnitude of all the planets and the spheres and the heaven itself, that in no single part could one thing be altered without confusion among the other parts and in all the universe. Hence for this reason in the course of this work I have followed this system.

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Johannes Kepler 51

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