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Home > Category Index for Science Quotations > Category Index G > Category: Gravity

Gravity Quotes (89 quotes)


'Tis a short sight to limit our faith in laws to those of gravity, of chemistry, of botany, and so forth. Those laws do not stop where our eyes lose them, but push the same geometry and chemistry up into the invisible plane of social and rational life, so that, look where we will, in a boy's game, or in the strifes of races, a perfect reaction, a perpetual judgment keeps watch and ward.
From 'Worship', The Conduct of Life (1860) collected in The Complete Works of Ralph Waldo Emerson (1866), Vol.2, 401.
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Dilbert: And we know mass creates gravity because more dense planets have more gravity.
Dogbert: How do we know which planets are more dense?
Dilbert:They have more gravity.
Dogbert: That's circular reasoning.
Dilbert: I prefer to think of it as having no loose ends.
Dilbert cartoon strip (1 Mar 1999).
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Homo hominem arreptum a tellure, et utcunque exigua impulsum vi, vel uno etiam oris flatu impetitum, ab hominum omnium commercio in infinitum expelleret, nunquam per totam aeternitatem rediturum.
Were it not for gravity one man might hurl another by a puff of his breath into the depths of space, beyond recall for all eternity.
Philosophiae Naturalis Theoria (1758), Vol. 1, para. DXLIII, 293.

La chaleur pénètre, comme la gravité, toutes les substances de l’univers, ses rayons occupent toutes les parties de l’espace. Le but de notre ouvrage est d’exposer les lois mathématiques que suit cet élément. Cette théorie formera désormais une des branches les plus importantes de la physique générale.
Heat, like gravity, penetrates every substance of the universe, its rays occupy all parts of space. The object of our work is to set forth the mathematical laws which this element obeys. The theory of heat will hereafter form one of the most important branches of general physics.
From 'Discours Préliminaire' to Théorie Analytique de la Chaleur (1822), i, translated by Alexander Freeman in The Analytical Theory of Heat (1878), 1.
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A rock has no detectable opinion about gravity.
In Terry Pratchett, Ian Stewart and Jack Cohen, The Science of Discworld (2014), 10, footnote.
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All those who think it paradoxical that so great a weight as the earth should not waver or move anywhere seem to me to go astray by making their judgment with an eye to their own affects and not to the property of the whole. For it would not still appear so extraordinary to them, I believe, if they stopped to think that the earth's magnitude compared to the whole body surrounding it is in the ratio of a point to it. For thus it seems possible for that which is relatively least to be supported and pressed against from all sides equally and at the same angle by that which is absolutely greatest and homogeneous.
Ptolemy
'The Almagest 1', in Ptolemy: the Almagest; Nicolaus Copernicus: On the Revolutions of the Heavenly Spheres; Johannes Kepler: Epitome of Copernican Astronomy: IV - V The Harmonies of the World: V, trans. R. Catesby Taliaferro (1952), 11.
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And for rejecting such a Medium, we have the Authority of those the oldest and most celebrated Philosophers of Greece and Phoenicia, who made a Vacuum, and Atoms, and the Gravity of Atoms, the first Principles of their Philosophy; tacitly attributing Gravity to some other Cause than dense Matter. Later Philosophers banish the Consideration of such a Cause out of natural Philosophy, feigning Hypotheses for explaining all things mechanically, and referring other Causes to Metaphysicks: Whereas the main Business of natural Philosophy is to argue from Phaenomena without feigning Hypotheses, and to deduce Causes from Effects, till we come to the very first Cause, which certainly is not mechanical; and not only to unfold the Mechanism of the World, but chiefly to resolve these and such like Questions. What is there in places almost empty of Matter, and whence is it that the Sun and Planets gravitate towards one another, without dense Matter between them? Whence is it that Nature doth nothing in vain; and whence arises all that Order and Beauty which we see in the World? ... does it not appear from phaenomena that there is a Being incorporeal, living, intelligent, omnipresent, who in infinite space, as it were in his Sensory, sees the things themselves intimately, and thoroughly perceives them, and comprehends them wholly by their immediate presence to himself.
In Opticks, (1704, 2nd. Ed. 1718), Book 3, Query 28, 343-5.
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And make us as Newton was, who in his garden watching
The apple falling towards England, became aware
Between himself and her of an eternal tie.
'Prologue' in Look Stranger! (1936), 11.
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And thus Nature will be very conformable to her self and very simple, performing all the great Motions of the heavenly Bodies by the Attraction of Gravity which intercedes those Bodies, and almost all the small ones of their Particles by some other attractive and repelling Powers which intercede the Particles. The Vis inertiae is a passive Principle by which Bodies persist in their Motion or Rest, receive Motion in proportion to the Force impressing it, and resist as much as they are resisted. By this Principle alone there never could have been any Motion in the World. Some other Principle was necessary for putting Bodies into Motion; and now they are in Motion, some other Principle is necessary for conserving the Motion.
From Opticks, (1704, 2nd ed. 1718), Book 3, Query 31, 372-3.
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Any opinion as to the form in which the energy of gravitation exists in space is of great importance, and whoever can make his opinion probable will have, made an enormous stride in physical speculation. The apparent universality of gravitation, and the equality of its effects on matter of all kinds are most remarkable facts, hitherto without exception; but they are purely experimental facts, liable to be corrected by a single observed exception. We cannot conceive of matter with negative inertia or mass; but we see no way of accounting for the proportionality of gravitation to mass by any legitimate method of demonstration. If we can see the tails of comets fly off in the direction opposed to the sun with an accelerated velocity, and if we believe these tails to be matter and not optical illusions or mere tracks of vibrating disturbance, then we must admit a force in that direction, and we may establish that it is caused by the sun if it always depends upon his position and distance.
Letter to William Huggins (13 Oct 1868). In P. M. Hannan (ed.), The Scientific Letters and Papers of James Clerk Maxwell (1995), Vol. 2, 1862-1873, 451-2.
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Architecture is of all the arts the one nearest to a science, for every architectural design is at its inception dominated by scientific considerations. The inexorable laws of gravitation and of statics must be obeyed by even the most imaginative artist in building.
Anonymous
In 'The Message of Greek Architecture', The Chautauquan (Apr 1906), 43, 110.
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As he sat alone in a garden, he [Isaac Newton in 1666, age 24] fell into a speculation on the power of gravity; that as this power is not found sensibly diminished at the remotest distance from the centre of the earth to which we can rise, neither at the tops of the loftiest buildings, nor even on the summits of the highest mountains, it appeared to him reasonable to conclude that this power must extend much further than was usually thought: why not as high as the moon? said he to himself; and if so, her motion must be influenced by it; perhaps she is retained in her orbit thereby.
View of Newton's Philosophy (1728), preface. In William Whewell, History of the Inductive Sciences (1847), Vol. 2, 166. Pemberton's narrative is based on firsthand conversations with Newton himself.
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As soon as matter took over, the force of Newtonian gravity, which represents one of the most important characteristics of “ponderable” matter, came into play.
In Conclusion of The Creation of the Universe (1952, 2012), 136.
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As true as steel, as plantage to the moon,
As sun to day, at turtle to her mate,
As iron to adamant, as earth to centre.
Character Troilus speaking to Cressida, in play Troilus and Cressida (c.1601), Act 3, lines 352-354. In Troilus and Cressida (1811), 72.
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But as a philosopher said, one day after mastering the winds, the waves, the tides and gravity, after all the scientific and technological achievements, we shall harness for God the energies of love. And then, for the second time in the history of the world, man will have discovered fire.
Speech accepting nomination as candidate for vice president, Democratic National Committee, Washington, D.C. (8 Aug 1972) as reported in New York Times (9 Aug 1972), 18. Shriver slightly paraphrased the similar sentiment written in 1934 by Pierre Teilhard de Chardin, translated by René Hague in 'The Evolution of Chastity', Toward the Future (1975), 86-87.
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But shall gravity be therefore called an occult cause, and thrown out of philosophy, because the cause of gravity is occult and not yet discovered? Those who affirm this, should be careful not to fall into an absurdity that may overturn the foundations of all philosophy. For causes usually proceed in a continued chain from those that are more compounded to those that are more simple; when we are arrived at the most simple cause we can go no farther ... These most simple causes will you then call occult and reject them? Then you must reject those that immediately depend on them.
Mathematical Principles (1729), 27.

But the strong base and building of my love
Is as the very centre of the earth,
Drawing all things to 't.
Character Cressidus to Pandarus in play Troilus and Cressida (c.1601), Act 4, lines 200-202. In Troilus and Cressida (1811), 92.
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But when we face the great questions about gravitation Does it require time? Is it polar to the 'outside of the universe' or to anything? Has it any reference to electricity? or does it stand on the very foundation of matter–mass or inertia? then we feel the need of tests, whether they be comets or nebulae or laboratory experiments or bold questions as to the truth of received opinions.
Letter to Michael Faraday, 9 Nov 1857. In P. M. Harman (ed.), The Scientific Letters and Papers of James Clerk Maxwell (1990), Vol. 1, 1846-1862, 551-2.
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Considering the difficulties represented by the lack of water, by extremes of temperature, by the full force of gravity unmitigated by the buoyancy of water, it must be understood that the spread to land of life forms that evolved to meet the conditions of the ocean represented the greatest single victory won by life over the inanimate environment.
(1965). In Isaac Asimov’s Book of Science and Nature Quotations (1988), 194.
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First, [Newton’s Law of Universal Gravitation] is mathematical in its expression…. Second, it is not exact; Einstein had to modify it…. There is always an edge of mystery, always a place where we have some fiddling around to do yet…. But the most impressive fact is that gravity is simple…. It is simple, and therefore it is beautiful…. Finally, comes the universality of the gravitational law and the fact that it extends over such enormous distances…
In The Character of Physical Law (1965, 2001), 33.
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For the better part of my last semester at Garden City High, I constructed a physical pendulum and used it to make a “precision” measurement of gravity. The years of experience building things taught me skills that were directly applicable to the construction of the pendulum. Twenty-five years later, I was to develop a refined version of this measurement using laser-cooled atoms in an atomic fountain interferometer.
[Outcome of high school physics teacher, Thomas Miner, encouraging Chu's ambitious laboratory project.]
Autobiography in Gösta Ekspong (ed.), Nobel Lectures: Physics 1996-2000 (2002), 116.
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From birth, man carries the weight of gravity on his shoulders. He is bolted to earth. But man has only to sink beneath the surface and he is free.
Quoted in 'Sport: Poet of the Depths', Time (28 Mar 1960)
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General Theory of Relativity = Gravity too; referentially, eh?
Anagram
Anagram by V. Rabin (2003) on anagramgenius.com website.
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Gravity is a contributing factor in nearly 73 percent of all accidents involving falling objects.
Syndicated column, 'Problems Of Utmost Gravity', seen, for example, in the Chicago Tribune (15 Mar 1998).
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Gravity is only the bark of wisdom’s tree, but it preserves it.
Confucius
In Samuel Arthur Bent, Short Sayings of Great Men (1882), 159
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Gravity tells us why an apple doesn’t go to heaven.
Anonymous
In Cecil Hunt, The Best Howlers (1957).
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Gravity, a mere nuisance to Christian, was a terror to Pope, Pagan, and Despair. You can drop a mouse down a thousand-yard mine shaft; and, on arriving at the bottom, it gets a slight shock and walks away, provided that the ground is fairly soft. A rat is killed, a man is broken, a horse splashes.
Essay, 'On Being the Right Size', collected in Possible Worlds: And Other Essays (1927, 1945), 19. (Note: Christian appears in John Bunyan, Pilgrim’s Progress, in which Pope, Pagan and Despair are giants — Webmaster.)
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Historical science is not worse, more restricted, or less capable of achieving firm conclusions because experiment, prediction, and subsumption under invariant laws of nature do not represent its usual working methods. The sciences of history use a different mode of explanation, rooted in the comparative and observational richness in our data. We cannot see a past event directly, but science is usually based on inference, not unvarnished observation (you don’t see electrons, gravity, or black holes either).
…...
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I always rejoice to hear of your being still employed in experimental researches into nature, and of the success you meet with. The rapid progress true science now makes, occasions my regretting sometimes that I was born so soon: it is impossible to imagine the height to which may be carried, in a thousand years, the power of man over matter; we may perhaps learn to deprive large masses of their gravity, and give them absolute levity for the sake of easy transport. Agriculture may diminish its labour and double its produce; all diseases may by sure means be prevented or cured (not excepting even that of old age), and our lives lengthened at pleasure even beyond the antediluvian standard. Oh! that moral science were in as fair a way of improvement; that men would cease to be wolves to one another; and that human beings would at length learn what they now improperly call humanity!
Letter to Dr Priestley, 8 Feb 1780. In Memoirs of Benjamin Franklin (1845), Vol. 2, 152.
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I experimented with all possible maneuvers—loops, somersaults and barrel rolls. I stood upside down on one finger and burst out laughing, a shrill, distorted laugh. Nothing I did altered the automatic rhythm of the air. Delivered from gravity and buoyancy, I flew around in space.
Describing his early test (1943) in the Mediterranean Sea of the Aqua-Lung he co-invented.
Quoted in 'Sport: Poet of the Depths', Time (28 Mar 1960)
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I have never thought that you could obtain the extremely clumpy, heterogeneous universe we have today, strongly affected by plasma processes, from the smooth, homogeneous one of the Big Bang, dominated by gravitation.
Quoted in Anthony L. Peratt, 'Dean of the Plasma Dissidents', Washington Times, supplement: The World and I (May 1988),196.
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I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis, and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy.
Principia. In Isaac Newton, Andrew Motte and N. W. Chittenden, Newton’s Principia (1847), 506-507.
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I myself consider that gravity is merely a certain natural inclination with which parts are imbued by the architect of all things for gathering themselves together into a unity and completeness by assembling into the form of a globe. It is easy to believe that the Sun, Moon and other luminaries among the wandering stars have this tendency also, so that by its agency they retain the rounded shape in which they reveal themselves, but nevertheless go round their orbits in various ways. If then the Earth also performs other motions, as for example the one about the centre, they must necessarily be like those which are similarly apparent in many external bodies in which we find an annual orbit.
'Book One. Chapter IX. Whether several motions can be attributed to the Earth, and on the centre of the universe', in Copernicus: On the Revolutions of the Heavenly Spheres (1543), trans. A. M. Duncan (1976), 46.

I was sitting in a chair in the patent office at Bern when all of a sudden a thought occurred to me: “If a person falls freely he will not feel his own weight.” I was startled. This simple thought made a deep impression on me. It impelled me toward a theory of gravitation.
Lecture in Japan (1922). The quote is footnoted in Michael White, John Gribbin, Einstein: a Life in Science (1995), 128, saying the talk is known as the 'Kyoto address', reported in J. Ishiwara, Einstein Koen-Roku (1977).
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If you are out to describe the truth, leave elegance to the tailor.
On being reproached that his formula of gravitation was longer and more cumbersome than Newton’s.
Quoted in J. H. Mitchell, Writing for Professional and Technical Journals (1968), Introduction.
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In 1684 Dr Halley came to visit him at Cambridge, after they had been some time together, the Dr asked him what he thought the Curve would be that would be described by the Planets supposing the force of attraction towards the Sun to be reciprocal to the square of their distance from it. Sr Isaac replied immediately that it would be an Ellipsis, the Doctor struck with joy & amazement asked him how he knew it, why saith he I have calculated it, whereupon Dr Halley asked him for his calculation without any farther delay. Sr Isaac looked among his papers but could not find it, but he promised him to renew it, & then to send it him.
[Recollecting Newton's account of the meeting after which Halley prompted Newton to write The Principia. When asking Newton this question, Halley was aware, without revealing it to Newton that Robert Hooke had made this hypothesis of plantary motion a decade earlier.]
Quoted in Richard Westfall, Never at Rest: A Biography of Isaac Newton (1980), 403.
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In general I would be cautious against … plays of fancy and would not make way for their reception into scientific astronomy, which must have quite a different character. Laplace’s cosmogenic hypotheses belong in that class. Indeed, I do not deny that I sometimes amuse myself in a similar manner, only I would never publish the stuff. My thoughts about the inhabitants of celestial bodies, for example, belong in that category. For my part, I am (contrary to the usual opinion) convinced … that the larger the cosmic body, the smaller are the inhabitants and other products. For example, on the sun trees, which in the same ratio would be larger than ours, as the sun exceeds the earth in magnitude, would not be able to exist, for on account of the much greater weight on the surface of the sun, all branches would break themselves off, in so far as the materials are not of a sort entirely heterogeneous with those on earth.
Letter to Heinrich Schumacher (7 Nov 1847). Quoted in G. Waldo Dunnington, Carl Friedrich Gauss: Titan of Science (2004), 411.
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In the beginning of the year 1665 I found the Method of approximating series & the Rule for reducing any dignity of any Bionomial 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 Keplers 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.
Quoted in Richard Westfall, Never at Rest: A Biography of Isaac Newton (1980), 143.
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In the infancy of physical science, it was hoped that some discovery might be made that would enable us to emancipate ourselves from the bondage of gravity, and, at least, pay a visit to our neighbour the moon. The poor attempts of the aeronaut have shewn the hopelessness of the enterprise. The success of his achievement depends on the buoyant power of the atmosphere, but the atmosphere extends only a few miles above the earth, and its action cannot reach beyond its own limits. The only machine, independent of the atmosphere, we can conceive of, would be one on the principle of the rocket. The rocket rises in the air, not from the resistance offered by the atmosphere to its fiery stream, but from the internal reaction. The velocity would, indeed, be greater in a vacuum than in the atmosphere, and could we dispense with the comfort of breathing air, we might, with such a machine, transcend the boundaries of our globe, and visit other orbs.
God's Glory in the Heavens (1862, 3rd Ed. 1867) 3-4.
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In the year 1666 he retired again from Cambridge... to his mother in Lincolnshire & whilst he was musing in a garden it came into his thought that the power of gravity (wch brought an apple from the tree to the ground) was not limited to a certain distance from the earth but that this power must extend much farther than was usually thought. Why not as high as the moon said he to himself & if so that must influence her motion & perhaps retain her in her orbit, whereupon he fell a calculating what would be the effect of that supposition but being absent from books & taking the common estimate in use among Geographers & our seamen before Norwood had measured the earth, that 60 English miles were contained in one degree of latitude on the surface of the Earth his computation did not agree with his theory & inclined him then to entertain a notion that together with the force of gravity there might be a mixture of that force wch the moon would have if it was carried along in a vortex.
[The earliest account of Newton, gravity and an apple.]
Memorandum of a conversation with Newton in August 1726. Quoted in Richard Westfall, Never at Rest: A Biography of Isaac Newton (1980), 154.
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In this lecture I would like to conclude with … some characteristics [of] gravity … The most impressive fact is that gravity is simple. It is simple to state the principles completely and not have left any vagueness for anybody to change the ideas of the law. It is simple, and therefore it is beautiful. It is simple in its pattern. I do not mean it is simple in its action—the motions of the various planets and the perturbations of one on the other can be quite complicated to work out, and to follow how all those stars in a globular cluster move is quite beyond our ability. It is complicated in its actions, but the basic pattern or the system beneath the whole thing is simple. This is common to all our laws; they all turn out to be simple things, although complex in their actual actions.
In 'The Law of Gravitation, as Example of Physical Law', the first of his Messenger Lectures (1964), Cornell University. Collected in The Character of Physical Law (1967), 33-34.
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Is it not true that the doctrine of attraction and gravity has done nothing but astonish our imagination? Is it not true that all chemical discoveries have done only the same?
Letter to Jean le Rond D'Alembert (7 Jan 1768). Collected in Correspondence: Letters Between Frederick II and M. D’Alembert (1789), 79, as translated by Thomas Holcroft.
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It is a mathematical fact that the casting of a pebble from my hand alters the centre of gravity of the universe.
In James Wood, Dictionary of Quotations from Ancient and Modern, English and Foreign Sources (1893), 190:1.
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It is inconceivable, that inanimate brute matter should, without the mediation of something else, which is not material, operate upon and affect other matter without mutual contact … That gravity should be innate, inherent, and essential to matter, so that one body may act upon another at a distance, through a vacuum, without the mediation of anything else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity, that I believe no man who has in philosophical matters a competent faculty of thinking, can ever fall into it. Gravity must be caused by an agent, acting constantly according to certain laws; but whether this agent be material or immaterial, I have left to the consideration of my readers.
Third letter to Bentley, 25 Feb 1693. Quoted in The Works of Richard Bentley, D.D. (1838), Vol. 3, 212-3.

It is most interesting to observe into how small a field the whole of the mysteries of nature thus ultimately resolve themselves. The inorganic has one final comprehensive law, GRAVITATION. The organic, the other great department of mundane things, rests in like manner on one law, and that is,—DEVELOPMENT. Nor may even these be after all twain, but only branches of one still more comprehensive law, the expression of that unity which man's wit can scarcely separate from Deity itself.
Vestiges of the Natural History of Creation (1844), 360.
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It must have appeared almost as improbable to the earlier geologists, that the laws of earthquakes should one day throw light on the origin of mountains, as it must to the first astronomers, that the fall of an apple should assist in explaining the motions of the moon.
Principles of Geology(1830-3), Vol. 3, 5.
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It seems to me farther, that these Particles have not only a Vis inertiae, accompanied with such passive Laws of Motion as naturally result from that Force, but also that they are moved by certain active Principles, such as that of Gravity, and that which causes Fermentation, and the Cohesion of Bodies. These Principles I consider, not as occult Qualities, supposed to result from the specifick Forms of Things, but as general Laws of Nature, by which the Things themselves are form'd; their Truth appearing to us by Phaenomena, though their Causes be not yet discover'd. For these are manifest Qualities, and their Causes only are occult.
From Opticks, (1704, 2nd ed. 1718), Book 3, Query 31, 376-377.
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Man must at all costs overcome the Earth’s gravity and have, in reserve, the space at least of the Solar System. All kinds of danger wait for him on the Earth… We are talking of disaster that can destroy the whole of mankind or a large part of it… For instance, a cloud of bolides [meteors] or a small planet a few dozen kilometers in diameter could fall on the Earth, with such an impact that the solid, liquid or gaseous blast produced by it could wipe off the face of the Earth all traces of man and his buildings. The rise of temperature accompanying it could alone scorch or kill all living beings… We are further compelled to take up the struggle against gravity, and for the utilization of celestial space and all its wealth, because of the overpopulation of our planet. Numerous other terrible dangers await mankind on the Earth, all of which suggest that man should look for a way into the Cosmos. We have said a great deal about the advantages of migration into space, but not all can be said or even imagined.
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NEWTONIAN, adj. Pertaining to a philosophy of the universe, invented by Newton, who discovered that an apple will fall to the ground, but was unable to say why. His successors and disciples have advanced so far as to be able to say when.
The Collected Works of Ambrose Bierce (1911), Vol. 7, The Devil's Dictionary,  228.
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No other theory known to science [other than superstring theory] uses such powerful mathematics at such a fundamental level. …because any unified field theory first must absorb the Riemannian geometry of Einstein’s theory and the Lie groups coming from quantum field theory… The new mathematics, which is responsible for the merger of these two theories, is topology, and it is responsible for accomplishing the seemingly impossible task of abolishing the infinities of a quantum theory of gravity.
In 'Conclusion', Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the Tenth Dimension (1995), 326.
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Now it came to me: … the independence of the gravitational acceleration from the nature of the falling substance, may be expressed as follows: In a gravitational field (of small spatial extension) things behave as they do in a space free of gravitation. … This happened in 1908. Why were another seven years required for the construction of the general theory of relativity? The main reason lies in the fact that it is not so easy to free oneself from the idea that coordinates must have an immediate metrical meaning.
In Paul Arthur Schilpp, 'Autobiographical Notes', Albert Einstein: Philosopher-Scientist (1949), 65-67.
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Obvious facts are apt to be over-rated. System-makers see the gravitation of history, and fail to observe its chemistry, of greater though less evident power.
From chapter 'Jottings from a Note-book', in Canadian Stories (1918), 179.
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One summer day, while I was walking along the country road on the farm where I was born, a section of the stone wall opposite me, and not more than three or four yards distant, suddenly fell down. Amid the general stillness and immobility about me the effect was quite startling. ... It was the sudden summing up of half a century or more of atomic changes in the material of the wall. A grain or two of sand yielded to the pressure of long years, and gravity did the rest.
Under the Apple-Trees (1916), 105.
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Our two greatest problems are gravity and paperwork. We can lick gravity, but sometimes the paperwork is overwhelming.
In the Chicago Sun Times (10 Jul 1958)
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People do more talking than listening: under the law of gravity, it takes more energy to shut one's mouth than to open it.
Anonymous
In Evan Esar, 20,000 Quips and Quotes, 267.
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Pick a flower on Earth and you move the farthest star.
As given, without citation, in Paul G. Hewitt, Conceptual Physics (4th ed., 1981), 51, footnote.
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Science has thus, most unexpectedly, placed in our hands a new power of great but unknown energy. It does not wake the winds from their caverns; nor give wings to water by the urgency of heat; nor drive to exhaustion the muscular power of animals; nor operate by complicated mechanism; nor summon any other form of gravitating force, but, by the simplest means—the mere contact of metallic surfaces of small extent, with feeble chemical agents, a power everywhere diffused through nature, but generally concealed from our senses, is mysteriously evolved, and by circulation in insulated wires, it is still more mysteriously augmented, a thousand and a thousand fold, until it breaks forth with incredible energy.
Comment upon 'The Notice of the Electro-Magnetic Machine of Mr. Thomas Davenport, of Brandon, near Rutland, Vermont, U.S.', The Annals of Electricity, Magnetism, & Chemistry; and Guardian of Experimental Science (1838), 2, 263.
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Seeing therefore the variety of Motion which we find in the World is always decreasing, there is a necessity of conserving and recruiting it by active Principles, such as are the cause of Gravity, by which Planets and Comets keep their Motions in their Orbs, and Bodies acquire great Motion in falling; and the cause of Fermentation, by which the Heart and Blood of Animals are kept in perpetual Motion and Heat; the inward Parts of the Earth are constantly warm'd, and in some places grow very hot; Bodies burn and shine, Mountains take fire, the Caverns of the Earth are blown up, and the Sun continues violently hot and lucid, and warms all things by his Light. For we meet with very little Motion in the World, besides what is owing to these active Principles.
From Opticks, (1704, 2nd ed. 1718), Book 3, Query 31, 375.
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She has the sort of body you go to see in marble. She has golden hair. Quickly, deftly, she reaches with both hands behind her back and unclasps her top. Setting it on her lap, she swivels ninety degrees to face the towboat square. Shoulders back, cheeks high, she holds her pose without retreat. In her ample presentation there is defiance of gravity. There is no angle of repose. She is a siren and these are her songs.
…...
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Simple as the law of gravity now appears, and beautifully in accordance with all the observations of past and of present times, consider what it has cost of intellectual study. Copernicus, Galileo, Kepler, Euler, Lagrange, Laplace, all the great names which have exalted the character of man, by carrying out trains of reasoning unparalleled in every other science; these, and a host of others, each of whom might have been the Newton of another field, have all labored to work out, the consequences which resulted from that single law which he discovered. All that the human mind has produced—the brightest in genius, the most persevering in application, has been lavished on the details of the law of gravity.
in The Ninth Bridgewater Treatise: A Fragment (1838), 57.
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So then Gravity may put ye Planets into Motion, but without ye divine Power it could never put them into such a Circulating Motion as they have about ye Sun; & therefore, for this, as well as other Reasons, I am compelled to ascribe ye Frame of this Systeme to an intelligent agent.
Letter to Richard Bently (17 Jan 1693). 189.R.4.47, f. 5A, Trinity College Library, Cambridge.
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The cases of action at a distance are becoming, in a physical point of view, daily more and more important. Sound, light, electricity, magnetism, gravitation, present them as a series.
The nature of sound and its dependence on a medium we think we understand, pretty well. The nature of light as dependent on a medium is now very largely accepted. The presence of a medium in the phenomena of electricity and magnetism becomes more and more probable daily. We employ ourselves, and I think rightly, in endeavouring to elucidate the physical exercise of these forces, or their sets of antecedents and consequents, and surely no one can find fault with the labours which eminent men have entered upon in respect of light, or into which they may enter as regards electricity and magnetism. Then what is there about gravitation that should exclude it from consideration also? Newton did not shut out the physical view, but had evidently thought deeply of it; and if he thought of it, why should not we, in these advanced days, do so too?
Letter to E. Jones, 9 Jun 1857. In Michael Faraday, Bence Jones (ed.), The Life and Letters of Faraday (1870), Vol. 2, 387.
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The fact that we live at the bottom of a deep gravity well, on the surface of a gas covered planet going around a nuclear fireball 90 million miles away and think this to be normal is obviously some indication of how skewed our perspective tends to be.
In The Salmon of Doubt: Hitchhiking the Galaxy One Last Time (2002), 132.
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The first quality we know in matter is centrality,—we call it gravity,—which holds the universe together, which remains pure and indestructible in each mote, as in masses and planets, and from each atom rays out illimitable influence. To this material essence answers Truth, in the intellectual world,—Truth, whose centre is everywhere, and its circumference nowhere, whose existence we cannot disimagine,—the soundness and health of things, against which no blow can be struck but it recoils on the striker,—Truth, on whose side we always heartily are. And the first measure of a mind is its centrality, its capacity of truth, and its adhesion to it.
In 'Progress of Culture', an address read to the Phi Beta Kappa Society at Cambridge, 18 July 1867. Collected in Works of Ralph Waldo Emerson (1883), 477.
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The floating vapour is just as true an illustration of the law of gravity as the falling avalanche.
The Century Illustrated Monthly Magazine, May 1883 to October 1883 (1883), 26, 539.
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The force of gravity—though it is the first force with which we are acquainted, and though it is always with us, and though it is the one with a strength we most thoroughly appreciate—is by far the weakest known force in nature. It is first and rearmost.
In Asimov On Physics (1976, 1988), 56. Also in Isaac Asimov’s Book of Science and Nature Quotations (1988), 113.
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The sun has lost no beams, the earth no elements ; gravity is as adhesive, heat as expansive, light as joyful, air as virtuous, water as medicinal as on the first day. There is no loss, only transference. When the heat is less here it is not lost, but more heat is there.
In 'Perpetual Forces', North American Review (1877), No. 125. Collected in Ralph Waldo Emerson and James Elliot Cabot (ed.), Lectures and Biographical Sketches (1883), 61.
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The supposed astronomical proofs of the theory [of relativity], as cited and claimed by Einstein, do not exist. He is a confusionist. The Einstein theory is a fallacy. The theory that ether does not exist, and that gravity is not a force but a property of space can only be described as a crazy vagary, a disgrace to our age.
Quoted in Elizabeth Dilling, A "Who's Who" and Handbook of Radicalism for Patriots (1934), 49.
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The weight of any heavy body of known weight at a particular distance from the center of the world varies according to the variation of its distance therefrom: so that as often as it is removed from the center, it becomes heavier, and when brought near to it, is lighter. On this account, the relation of gravity to gravity is as the relation of distance to distance from the center.
From Book of the Balance of Wisdom. As cited in an epigraph in Charles W. Misner, Kip S. Thorne and John Archibald Wheeler, Gravity (1973), 37.
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The worlds of our solar system are widely different, but all share a common gravitational tie to the sun.
Epigraph in Isaac Asimov’s Book of Science and Nature Quotations (1988), 218.
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There are something like ten million million million million million million million million million million million million million million (1 with eighty zeroes after it) particles in the region of the universe that we can observe. Where did they all come from? The answer is that, in quantum theory, particles can be created out of energy in the form of particle/antiparticle pairs. But that just raises the question of where the energy came from. The answer is that the total energy of the universe is exactly zero. The matter in the universe is made out of positive energy. However, the matter is all attracting itself by gravity. Two pieces of matter that are close to each other have less energy than the same two pieces a long way apart, because you have to expend energy to separate them against the gravitational force that is pulling them together. Thus, in a sense, the gravitational field has negative energy. In the case of a universe that is approximately uniform in space, one can show that this negative gravitational energy exactly cancels the positive energy represented by the matter. So the total energy of the universe is zero.
A Brief History of Time: From the Big Bang to Black Holes (1988), 129.
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There is no gravity. The earth sucks.
Anonymous
…...
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Therefore the solid body of the earth is reasonably considered as being the largest relative to those moving against it and as remaining unmoved in any direction by the force of the very small weights, and as it were absorbing their fall. And if it had some one common movement, the same as that of the other weights, it would clearly leave them all behind because of its much greater magnitude. And the animals and other weights would be left hanging in the air, and the earth would very quickly fallout of the heavens. Merely to conceive such things makes them appear ridiculous.
Ptolemy
'The Almagest 1', in Ptolemy: the Almagest; Nicolaus Copernicus: On the Revolutions of the Heavenly Spheres; Johannes Kepler: Epitome of Copernican Astronomy: IV - V The Harmonies of the World: V, trans. R. Catesby Taliaferro (1952), 11.
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There’s very good news from the asteroids. It appears that a large fraction of them, including the big ones, are actually very rich in H2O. Nobody imagined that. They thought they were just big rocks … It’s easier to get to an asteroid than to Mars, because the gravity is lower and landing is easier. Certainly the asteroids are much more practical, right now. If we start space colonies in, say, the next 20 years, I would put my money on the asteroids.
As quoted in Kenneth Brower, 'The Danger of Cosmic Genius', The Atlantic (Dec 2010).
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They often say, “What’s the point in astrology if you can’t change your destiny?” Well, it’s true that you can’t change your destiny, but still it helps knowing about gravity.
Quotations: Superultramodern Science and Philosophy (2005), 1
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Those who would legislate against the teaching of evolution should also legislate against gravity, electricity and the unreasonable velocity of light, and also should introduce a clause to prevent the use of the telescope, the microscope and the spectroscope or any other instrument of precision which may in the future be invented ,constructed or used for the discovery of truth.
In 'Science and Civilization', Prescott Evening Courier (3 Nov 1925), 6.
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Thus far I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity. Indeed, this force arises from some cause that penetrates as far as the centers of the sun and planets without any diminution of its power to act, and that acts not in proportion to the quantity of the surfaces of the particles on which it acts (as mechanical causes are wont to do) but in proportion to the quantity of solid matter, and whose action is extended everywhere to immense distances, always decreasing as the squares of the distances.
The Principia: Mathematical Principles of Natural Philosophy (1687), 3rd edition (1726), trans. I. Bernard Cohen and Anne Whitman (1999), General Scholium, 943.
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Thus the system of the world only oscillates around a mean state from which it never departs except by a very small quantity. By virtue of its constitution and the law of gravity, it enjoys a stability that can be destroyed only by foreign causes, and we are certain that their action is undetectable from the time of the most ancient observations until our own day. This stability in the system of the world, which assures its duration, is one of the most notable among all phenomena, in that it exhibits in the heavens the same intention to maintain order in the universe that nature has so admirably observed on earth for the sake of preserving individuals and perpetuating species.
'Sur l'Équation Séculaire de la Lune' (1786, published 1788). In Oeuvres complètes de Laplace, 14 Vols. (1843-1912), Vol. 11, 248-9, trans. Charles Coulston Gillispie, Pierre-Simon Laplace 1749-1827: A Life in Exact Science (1997), 145.
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Today scientists describe the universe in terms of two basic partial theories—the general theory of relativity and quantum mechanics. They are the great intellectual achievements of the first half of this century. The general theory of relativity describes the force of gravity and the large-scale structure of the universe, that is, the structure on scales from only a few miles to as large as a million million million million (1 with twenty-four zeros after it) miles, the size of the observable universe. Quantum mechanics, on the other hand, deals with phenomena on extremely small scales, such as a millionth of a millionth of an inch. Unfortunately, however, these two theories are known to be inconsistent with each other—they cannot both be correct.
A Brief History of Time: From the Big Bang to Black Holes (1988), 11-2.
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We all know we fall. Newton’s discovery was that the moon falls, too—and by the same rule that we do.
Epigraph in Isaac Asimov’s Book of Science and Nature Quotations (1988), 112.
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We may also draw a very important additional conclusion from the gradual dissolution of the milky way; for the state into which the incessant action of the clustering power [presumably, gravity] has brought it at present, is a kind of chronometer that may be used to measure the time of its past and future existence; and although we do not know the rate of going of this mysterious chronometer, it is nevertheless certain, that since the breaking up of the parts of the milky way affords a proof that it cannot last for ever, it equally bears witness that its past duration cannot be admitted to the infinite.
'Astronomical Observations... ' Philosophical Transactions (1814), 104, 284.
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We see only the simple motion of descent, since that other circular one common to the Earth, the tower, and ourselves remains imperceptible. There remains perceptible to us only that of the stone, which is not shared by us; and, because of this, sense shows it as by a straight line, always parallel to the tower, which is built upright and perpendicular upon the terrestrial surface.
Dialogue on the Great World Systems (1632). Revised and Annotated by Giorgio De Santillana (1953), 177.
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What agencies of electricity, gravity, light, affinity combine to make every plant what it is, and in a manner so quiet that the presence of these tremendous powers is not ordinarily suspected. Faraday said, “ A grain of water is known to have electric relations equivalent to a very powerful flash of lightning.”
In 'Perpetual Forces', North American Review (1877), No. 125. Collected in Ralph Waldo Emerson and James Elliot Cabot (ed.), Lectures and Biographical Sketches (1883), 60.
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What doth gravity out of his bed at midnight?
…...
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What keeps us on this globe except force of gravity?
Unkempt Thoughts (1962), 34.
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When Newton saw an apple fall, he found
In that slight startle from his contemplation—
'Tis said (for I'll not answer above ground
For any sage's creed or calculation)—
A mode of proving that the earth turn'd round
In a most natural whirl, called 'gravitation';
And this is the sole mortal who could grapple,
Since Adam, with a fall, or with an apple.
Don Juan (1821), Canto 10, Verse I. In Jerome J. McGann (ed.), Lord Byron: The Complete Poetical Works (1986), Vol. 5, 437.
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When the movement of the comets is considered and we reflect on the laws of gravity, it will be readily perceived that their approach to Earth might there cause the most woeful events, bring back the deluge, or make it perish in a deluge of fire, shatter it into small dust, or at least turn it from its orbit, drive away its Moon, or, still worse, the Earth itself outside the orbit of Saturn, and inflict upon us a winter several centuries long, which neither men nor animals would be able to bear. The tails even of comets would not be unimportant phenomena, if in taking their departure left them in whole or part in our atmosphere
CosmoIogische Briefe über die Einrichtung des Weltbaues (1761). In Carl Sagan, Broca's Brain (1986), 95.
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You sometimes speak of gravity as essential and inherent to matter. Pray do not ascribe that notion to me, for the cause of gravity is what I do not pretend to know, and therefore would take more time to consider of it.
Letter to Dr. Bentley (17 Jan 1692). In Four Letters from Sir Isaac Newton to Doctor Bentley (1756), 20.
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[S]ome physicists describe gravity in terms of ten dimensions all curled up. But those aren't real words—just placeholders, used to refer to parts of abstract equations.
In God's Debris: A Thought Experiment (2004), 20-21.
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Carl Sagan Thumbnail In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. (1987) -- Carl Sagan
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