Quotes about geometry
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Manuel Castells photo
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Vitruvius photo
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Thomas Little Heath photo
George Biddell Airy photo
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François Englert photo

“Three distinct geometries on S7 arise as solutions of the classical equations of motion in eleven dimensions. In addition to the conventional riemannian geometry, one can also obtain the two exceptional Cartan-Schouten compact flat geometries with torsion.”

François Englert (1932) Belgian theoretical physicist

[10.1016/0370-2693(82)90684-0, 1982, Spontaneous compactification of eleven-dimensional supergravity, Physics Letters B, 119, 4–6, 339–342]

Jean Metzinger photo
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Brook Taylor photo
Omar Khayyám photo

“Whoever thinks algebra is a trick in obtaining unknowns has thought it in vain. No attention should be paid to the fact that algebra and geometry are different in appearance. Algebras (jabbre and maqabeleh) are geometric facts which are proved by propositions five and six of Book two of Elements.”

Omar Khayyám (1048–1131) Persian poet, philosopher, mathematician, and astronomer

As quoted in "A Paper of Omar Khayyam" by A.R. Amir-Moez in Scripta Mathematica 26 (1963). This quotation has often been abridged in various ways, usually ending with "Algebras are geometric facts which are proved", thus altering the context significantly.

Charles Dupin photo
Immanuel Kant photo
Hans Reichenbach photo
Diogenes Laërtius photo

“Very late in life, when he was studying geometry, some one said to Lacydes, "Is it then a time for you to be learning now?"”

Diogenes Laërtius (180–240) biographer of ancient Greek philosophers

"If it is not," he replied, "when will it be?"
Lacydes, 5.
The Lives and Opinions of Eminent Philosophers (c. 200 A.D.), Book 4: The Academy

Arthur Koestler photo

“We find in the history of ideas mutations which do not seem to correspond to any obvious need, and at first sight appear as mere playful whimsies — such as Apollonius' work on conic sections, or the non-Euclidean geometries, whose practical value became apparent only later.”

Arthur Koestler (1905–1983) Hungarian-British author and journalist

as quoted by Michael Grossman in the The First Nonlinear System of Differential and Integral Calculus (1979).
The Sleepwalkers: A History of Man's Changing Vision of the Universe (1959)

Albert Gleizes photo
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Lee Smolin photo
Florian Cajori photo

“It is a remarkable fact in the history of geometry, that the Elements of Euclid, written two thousand years ago, are still regarded by many as the best introduction to the mathematical sciences.”

Source: A History of Mathematics (1893), p. 30 Reported in Memorabilia mathematica or, The philomath's quotation-book by Robert Edouard Moritz. Published 1914.

Augustus De Morgan photo
Johannes Kepler photo

“Geometry is one and eternal shining in the mind of God. That share in it accorded to humans is one of the reasons that humanity is the image of God.”

Book III, Ch. 1 as quoted in "Astrology in Kepler's Cosmology" by Judith V. Field, in Astrology, Science, and Society: Historical Essays (1987) edited by P. Curry, p. 154
Geometry, coeternal with God and shining in the divine Mind, gave God the pattern... by which he laid out the world so that it might be best and most beautiful and finally most like the Creator.
As quoted in Kepler's Geometrical Cosmology (1988), p. 123
Geometry is one and eternal shining in the mind of God. That share in it accorded to men is one of the reasons that Man is the image of God.
Unsourced variant
Harmonices Mundi (1618)

“The philosophy of the foundations of probability must be divorced from mathematics and statistics, exactly as the discussion of our intuitive space concept is now divorced from geometry.”

William Feller (1906–1970) Croatian-American mathematician

Introduction, The Nature of Probability Theory, p. 3.
An Introduction To Probability Theory And Its Applications (Third Edition)

John Theophilus Desaguliers photo
Gerald James Whitrow photo
Vitruvius photo

“What would geometry be without Gauss, mathematical logic without Boole, algebra without Hamilton, analysis without Cauchy?”

George Frederick James Temple (1901–1992) British mathematician

100 Years of Mathematics: a Personal Viewpoint (1981)

Augustus De Morgan photo
Richard von Mises photo

“I am prepared to concede without further argument that all the theoretical constructions, including geometry, which are used in the various branches of physics are only imperfect instruments to enable the world of empirical fact to be reconstructed in our minds.”

Richard von Mises (1883–1953) Austrian physicist and mathematician

First Lecture, The Definition of Probability, p. 8
Probability, Statistics And Truth - Second Revised English Edition - (1957)

Hermann Weyl photo
Bernard Le Bovier de Fontenelle photo
Alain Daniélou photo

“Sanskrit is constructed like geometry and follows a rigorous logic. It is theoretically possible to explain the meaning of the words according to the combined sense of the relative letters, syllables and roots. Sanskrit has no meanings by connotations and consequently does not age. Panini's language is in no way different from that of Hindu scholars conferring in Sanskrit today.”

Alain Daniélou (1907–1994) French historian, musicologist, Indologist and expert on Shaivite Hinduism

Alain Danielou in: Virtue, Success, Pleasure, and Liberation: The Four Aims of Life in the Tradition of Ancient India https://books.google.co.in/books?id=IMSngEmfdS0C&pg=PA17, Inner Traditions / Bear & Co, 1 August 1993 , p. 17.

Hans Reichenbach photo
Francis Place photo
Arthur Honegger photo

“Music is geometry in time.”

Arthur Honegger (1892–1955) Swiss composer

I am a Composer (1951)

Paul Carus photo

“The truth is that other systems of geometry are possible, yet after all, these other systems are not spaces but other methods of space measurements. There is one space only, though we may conceive of many different manifolds, which are contrivances or ideal constructions invented for the purpose of determining space.”

Paul Carus (1852–1919) American philosopher

Science, Vol. 18 (1903), p. 106, as reported in Memorabilia Mathematica; or, The Philomath's Quotation-Book https://archive.org/stream/memorabiliamathe00moriiala#page/81/mode/2up, (1914), by Robert Edouard Moritz, p. 352

Nicomachus photo
André Maurois photo

“Pascal said that if geometry stirred us emotionally as much as politics we would not be able to expound it so well.”

André Maurois (1885–1967) French writer

Un Art de Vivre (The Art of Living) (1939), The Art of Friendship

Simone Weil photo

“Gregorian chant, Romanesque architecture, the Iliad, the invention of geometry were not, for the people through whom they were brought into being and made available to us, occasions for the manifestation of personality.”

Simone Weil (1909–1943) French philosopher, Christian mystic, and social activist

Source: Simone Weil : An Anthology (1986), Human Personality (1943), p. 55

Al-Biruni photo
Ursula K. Le Guin photo
E. W. Hobson photo

“A new point is determined in Euclidean Geometry exclusively in one of the three following ways:
Having given four points A, B, C, D, not all incident on the same straight line, then
(1) Whenever a point P exists which is incident both on (A, B) and on (C, D), that point is regarded as determinate.
(2) Whenever a point P exists which is incident both on the straight line (A, B) and on the circle C(D), that point is regarded as determinate.
(3) Whenever a point P exists which is incident on both the circles A(B), C(D), that point is regarded as determinate.
The cardinal points of any figure determined by a Euclidean construction are always found by means of a finite number of successive applications of some or all of these rules (1), (2) and (3). Whenever one of these rules is applied it must be shown that it does not fail to determine the point. Euclid's own treatment is sometimes defective as regards this requisite.
In order to make the practical constructions which correspond to these three Euclidean modes of determination, correponding to (1) the ruler is required, corresponding to (2) both ruler and compass, and corresponding to (3) the compass only.
…it is possible to develop Euclidean Geometry with a more restricted set of postulations. For example it can be shewn that all Euclidean constructions can be carried out by means of (3) alone…”

E. W. Hobson (1856–1933) British mathematician

Source: Squaring the Circle (1913), pp. 7-8

“Suppose then I want to give myself a little training in the art of reasoning; suppose I want to get out of the region of conjecture and probability, free myself from the difficult task of weighing evidence, and putting instances together to arrive at general propositions, and simply desire to know how to deal with my general propositions when I get them, and how to deduce right inferences from them; it is clear that I shall obtain this sort of discipline best in those departments of thought in which the first principles are unquestionably true. For in all 59 our thinking, if we come to erroneous conclusions, we come to them either by accepting false premises to start with—in which case our reasoning, however good, will not save us from error; or by reasoning badly, in which case the data we start from may be perfectly sound, and yet our conclusions may be false. But in the mathematical or pure sciences,—geometry, arithmetic, algebra, trigonometry, the calculus of variations or of curves,—we know at least that there is not, and cannot be, error in our first principles, and we may therefore fasten our whole attention upon the processes. As mere exercises in logic, therefore, these sciences, based as they all are on primary truths relating to space and number, have always been supposed to furnish the most exact discipline. When Plato wrote over the portal of his school. “Let no one ignorant of geometry enter here,” he did not mean that questions relating to lines and surfaces would be discussed by his disciples. On the contrary, the topics to which he directed their attention were some of the deepest problems,—social, political, moral,—on which the mind could exercise itself. Plato and his followers tried to think out together conclusions respecting the being, the duty, and the destiny of man, and the relation in which he stood to the gods and to the unseen world. What had geometry to do with these things? Simply this: That a man whose mind has not undergone a rigorous training in systematic thinking, and in the art of drawing legitimate inferences from premises, was unfitted to enter on the discussion of these high topics; and that the sort of logical discipline which he needed was most likely to be obtained from geometry—the only mathematical science which in Plato’s time had been formulated and reduced to a system. And we in this country [England] have long acted on the same principle. Our future lawyers, clergy, and statesmen are expected at the University to learn a good deal about curves, and angles, and numbers and proportions; not because these subjects have the smallest relation to the needs of their lives, but because in the very act of learning them they are likely to acquire that habit of steadfast and accurate thinking, which is indispensable to success in all the pursuits of life.”

Joshua Girling Fitch (1824–1903) British educationalist

Source: Lectures on Teaching, (1906), pp. 291-292

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Nicomachus photo

“If geometry exists, arithmetic must also needs be implied”

Nicomachus (60–120) Ancient Greek mathematician

Nicomachus of Gerasa: Introduction to Arithmetic (1926)
Context: If geometry exists, arithmetic must also needs be implied... But on the contrary 3, 4, and the rest might be 5 without the figures existing to which they give names. Hence arithmetic abolishes geometry along with itself, but is not abolished by it, and while it is implied by geometry, it does not itself imply geometry.<!--Book I, Chapter IV

Roger Shepard photo

“It may not be premature to propose that spatial imagination has evolved as a reflection of the physics and geometry of the external world.”

Roger Shepard (1929) American psychologist

L.A. Cooper and R.N. Shepard (1984). "Turning something over in the mind." Scientific American 251(6), 106-114; p. 114.
Context: In spite of some unresolved issues, the close match we have found between mental rotation and their counterparts in the physical world leads inevitably to speculations about the functions and origin of human spatial imagination. It may not be premature to propose that spatial imagination has evolved as a reflection of the physics and geometry of the external world. The rules that govern structures and motions in the physical world may, over evolutionary history, have been incorporated into human perceptual machinery, giving rise to demonstrable correspondences between mental imagery and its physical analogues.

Brook Taylor photo

“I make no difference between the Plane of the Horizon, and any other Plane whatsoever; for since Planes, as Planes, are alike in Geometry, it is most proper to consider them as so”

Brook Taylor (1685–1731) English mathematician

New Principles of Linear Perspective (1715, 1749)
Context: I make no difference between the Plane of the Horizon, and any other Plane whatsoever; for since Planes, as Planes, are alike in Geometry, it is most proper to consider them as so, and to explain their Properties in general, leaving the Artist himself to apply them in particular Cases, as Occasion requires.

Benjamin Peirce photo

“Ascend with me above the dust, above the cloud, to the realms of the higher geometry, where the heavens are never clouded”

Benjamin Peirce (1809–1880) American mathematician

Ben Yamen's Song of Geometry (1853)
Context: Ascend with me above the dust, above the cloud, to the realms of the higher geometry, where the heavens are never clouded; where there is no impure vapour, and no delusive or imperfect observation, where the new truths are already arisen, while they are yet dimly dawning on the world below; where the earth is a little planet; where the sun has dwindled to a star; where all the stars are lost in the Milky Way to which they belong; where the Milky Way is seen floating through space like any other nebula; where the whole great girdle of nebulae has diminished to an atom and has become as readily and completely submissive to the pen of the geometer, and the slave of his formula, as the single drop, which falls from the clouds, instinct with all the forces of the material world.

John Theophilus Desaguliers photo

“It is to Sir Isaac Newton's Application of Geometry to Philosophy, that we owe the routing of this Army of Goths and Vandals in the philosophical World;”

John Theophilus Desaguliers (1683–1744) French-born British natural philosopher and clergyman

Source: Course of Experimental Philosophy, 1745, p. vi: Preface
Context: It is to Sir Isaac Newton's Application of Geometry to Philosophy, that we owe the routing of this Army of Goths and Vandals in the philosophical World; which he has enriched with more and greater Discoveries, than all the Philosophers that went before him: And has laid such Foundations for future Acquisitions, that even after his Death, his Works still promote natural Knowledge. Before Sir Isaac, we had but wild Guesses at the Cause of the Motion of the Comets and Planets round the Sun', but now he has clearly deduced them from the universal Laws of Attraction (the Existence of which he has proved beyond Contradiction) and has shewn, that the seeming Irregularities of the Moon, which Astronomers were unable to express in Numbers, are but the just Consequences of the Actions of the Sun and Earth upon it, according to their different Positions. His Principles clear up all Difficulties of the various Phænomena of the Tides; and the true Figure of the Earth is now plainly shewn to be a flatted Spheroid higher at the Equator than the Poles, notwithstanding many Assertions and Conjectures to the contrary.

Benjamin Peirce photo

“There is proof enough furnished by every science, but by none more than geometry, that the world to which we have been allotted is peculiarly adapted to our minds, and admirably fitted to promote our intellectual progress.”

Benjamin Peirce (1809–1880) American mathematician

Ben Yamen's Song of Geometry (1853)
Context: There is proof enough furnished by every science, but by none more than geometry, that the world to which we have been allotted is peculiarly adapted to our minds, and admirably fitted to promote our intellectual progress. There can be no reasonable doubt that it was part of the Creator's plan. How easily might the whole order have been transposed! How readily might we have been assigned to some complicated system which our feeble and finite powers could not have unravelled!

Gustave Flaubert photo

“Everything one invents is true, you may be perfectly sure of that. Poetry is as precise as geometry.”

Gustave Flaubert (1821–1880) French writer (1821–1880)

14 August 1853
Correspondence, Letters to Madame Louise Colet

“Let us now explain the origin of geometry, as existing in the present age of the world. For the demoniacal Aristotle observes, that the same opinions often subsist among men, according to certain orderly revolutions of the world: and that sciences did not receive their first constitution in our times, nor in those periods which are known to us from historical tradition, but have appeared and vanished again in other revolutions of the universe; nor is it possible to say how often this has happened in past ages, and will again take place in the future circulations of time. But, because the origin of arts and sciences is to be considered according to the present revolution of the universe, we must affirm, in conformity with the most general tradition, that geometry was first invented by the Egyptians, deriving its origin from the mensuration of their fields: since this, indeed, was necessary to them, on account of the inundation of the Nile washing away the boundaries of land belonging to each. Nor ought It to seem wonderful, that the invention of this as well as of other sciences, should receive its commencement from convenience and opportunity. Since whatever is carried in the circle of generation proceeds from the imperfect to the perfect.”

Proclus (412–485) Greek philosopher

Chap. IV. On the Origin of Geometry, and its Inventors, pp. 98-99. Footnote (Taylor's): Aristotle was called demoniacal by the Platonic philosophers, in consequence of the encomium bestowed on him by his master, Plato, "That he was the dæmon of nature." Indeed, his great knowledge in things subject to the dominion of nature, well deserved this encomium, and the epithet divine, has been universally ascribed to Plato, from his profound knowledge of the intelligible world.
The Philosophical and Mathematical Commentaries of Proclus on the First Book of Euclid's Elements Vol. 1 (1788)

Benjamin Peirce photo

“I presume that to the uninitiated the formulae will appear cold and cheerless; but let it be remembered that, like other mathematical formulae, they find their origin in the divine source of all geometry.”

Preface.
Linear Associative Algebra (1882)
Context: I presume that to the uninitiated the formulae will appear cold and cheerless; but let it be remembered that, like other mathematical formulae, they find their origin in the divine source of all geometry. Whether I shall have the satisfaction of taking part in their exposition, or whether that will remain for some more profound expositor, will be seen in the future.

Freeman Dyson photo

“The right way to ask the question is: How does the concept of a point fit into the logical structure of Euclid's geometry? …It cannot be answered by a definition.”

Source: Infinite in All Directions (1988), Ch. 2 : Butterflies and Superstrings, p. 17
Context: Euclid... gave his famous definition of a point: "A point is that which has no parts, or which has no magnitude." …A point has no existence by itself. It exists only as a part of the pattern of relationships which constitute the geometry of Euclid. This is what one means when one says that a point is a mathematical abstraction. The question, What is a point? has no satisfactory answer. Euclid's definition certainly does not answer it. The right way to ask the question is: How does the concept of a point fit into the logical structure of Euclid's geometry?... It cannot be answered by a definition.

Edwin Abbott Abbott photo

“I resumed my seat, again exclaiming, "The boy is a fool, I say; 3³ can have no meaning in Geometry." At once there came a distinctly audible reply, "The boy is not a fool; and 3³ has an obvious Geometrical meaning."”

Source: Flatland: A Romance of Many Dimensions (1884), PART II: OTHER WORLDS, Chapter 15. Concerning a Stranger from Spaceland
Context: There I sat by my Wife's side, endeavouring to form a retrospect of the year 1999 and of the possibilities of the year 2000, but not quite able to shake off the thoughts suggested by the prattle of my bright little Hexagon. Only a few sands now remained in the half-hour glass. Rousing myself from my reverie I turned the glass Northward for the last time in the old Millennium; and in the act, I exclaimed aloud, "The boy is a fool."Straightway I became conscious of a Presence in the room, and a chilling breath thrilled through my very being. "He is no such thing," cried my Wife, "and you are breaking the Commandments in thus dishonouring your own Grandson." But I took no notice of her. Looking round in every direction I could see nothing; yet still I FELT a Presence, and shivered as the cold whisper came again. I started up. "What is the matter?" said my Wife, "there is no draught; what are you looking for? There is nothing." There was nothing; and I resumed my seat, again exclaiming, "The boy is a fool, I say; 3&sup3; can have no meaning in Geometry." At once there came a distinctly audible reply, "The boy is not a fool; and 3&sup3; has an obvious Geometrical meaning."

Pierre de Fermat photo

“I propose this theorem to be proved or problem to be solved. If they succeed in discovering the proof or solution, they will acknowledge that questions of this kind are not inferior to the more celebrated ones from geometry either for depth or difficulty or method of proof”

Pierre de Fermat (1601–1665) French mathematician and lawyer

Letter to Frénicle (1657) Oeuvres de Fermat Vol.II as quoted by Edward Everett Whitford, The Pell Equation http://books.google.com/books?id=L6QKAAAAYAAJ (1912)
Context: There is scarcely any one who states purely arithmetical questions, scarcely any who understands them. Is this not because arithmetic has been treated up to this time geometrically rather than arithmetically? This certainly is indicated by many works ancient and modern. Diophantus himself also indicates this. But he has freed himself from geometry a little more than others have, in that he limits his analysis to rational numbers only; nevertheless the Zetcica of Vieta, in which the methods of Diophantus are extended to continuous magnitude and therefore to geometry, witness the insufficient separation of arithmetic from geometry. Now arithmetic has a special domain of its own, the theory of numbers. This was touched upon but only to a slight degree by Euclid in his Elements, and by those who followed him it has not been sufficiently extended, unless perchance it lies hid in those books of Diophantus which the ravages of time have destroyed. Arithmeticians have now to develop or restore it. To these, that I may lead the way, I propose this theorem to be proved or problem to be solved. If they succeed in discovering the proof or solution, they will acknowledge that questions of this kind are not inferior to the more celebrated ones from geometry either for depth or difficulty or method of proof: Given any number which is not a square, there also exists an infinite number of squares such that when multiplied into the given number and unity is added to the product, the result is a square.

Benjamin Peirce photo

“Geometry, to which I have devoted my life, is honoured with the title of the Key of Sciences”

Benjamin Peirce (1809–1880) American mathematician

Ben Yamen's Song of Geometry (1853)
Context: Geometry, to which I have devoted my life, is honoured with the title of the Key of Sciences; but it is the Key of an ever open door which refuses to be shut, and through which the whole world is crowding, to make free, in unrestrained license, with the precious treasures within, thoughtless both of lock and key, of the door itself, and even of Science, to which it owes such boundless possessions, the New World included. The door is wide open and all may enter, but all do not enter with equal thoughtlessness. There are a few who wonder, as they approach, at the exhaustless wealth, as the sacred shepherd wondered at the burning bush of Horeb, which was ever burning and never consumed. Casting their shoes from off their feet and the world's iron-shod doubts from their understanding, these children of the faithful take their first step upon the holy ground with reverential awe, and advance almost with timidity, fearful, as the signs of Deity break upon them, lest they be brought face to face with the Almighty.

Solomon Lefschetz photo

“It was my lot to plant the harpoon of algebraic topology into the body of the whale of algebraic geometry.”

Solomon Lefschetz (1884–1972) American mathematician

[Carl C. Gaither, Alma E. Cavazos-Gaither, Gaither's Dictionary of Scientific Quotations: A Collection of Approximately 27,000 Quotations Pertaining to Archaeology, Architecture, Astronomy, Biology, Botany, Chemistry, Cosmology, Darwinism, Engineering, Geology, Mathematics, Medicine, Nature, Nursing, Paleontology, Philosophy, Physics, Probability, Science, Statistics, Technology, Theory, Universe, and Zoology, https://books.google.com/books?id=zQaCSlEM-OEC&pg=PA29, 5 January 2012, Springer Science & Business Media, 978-1-4614-1114-7, 29]

Jorge Luis Borges photo

“Time carries him as the river carries
A leaf in the downstream water.
No matter. The enchanted one insists
And shapes God with delicate geometry.”

Jorge Luis Borges (1899–1986) Argentine short-story writer, essayist, poet and translator, and a key figure in Spanish language literature

"Baruch Spinoza", as translated in Spinoza and Other Heretics: The Marrano of Reason (1989) by Yirmiyahu Yovel
Context: Time carries him as the river carries
A leaf in the downstream water.
No matter. The enchanted one insists
And shapes God with delicate geometry.
Since his illness, since his birth,
He goes on constructing God with the word.
The mightiest love was granted him
Love that does not expect to be loved.

John Stuart Mill photo

“Newton saw the truth of many propositions of geometry without reading the demonstrations, but not, we may be sure, without their flashing through his mind. A truth, or supposed truth, which is really the result of a very rapid inference, may seem to be apprehended intuitively. It has long been agreed by thinkers of the most opposite schools, that this mistake is actually made in so familiar an instance as that of the eyesight. There is nothing of which we appear to ourselves to be more directly conscious, than the distance of an object from us. Yet it has long been ascertained, that what is perceived by the eye, is at most nothing more than a variously coloured surface; that when we fancy we see distance, all we really see is certain variations of apparent size, and degrees of faintness of colour; and that our estimate of the object's distance from us is the result of a comparison (made with so much rapidity that we are unconscious of making it) between the size and colour of the object as they appear at the time, and the size and colour of the same or of similar objects as they appeared when close at hand, or when their degree of remoteness was known by other evidence.”

Source: A System of Logic (1843), p. 4
Context: [W]e may fancy that we see or feel what we in reality infer. Newton saw the truth of many propositions of geometry without reading the demonstrations, but not, we may be sure, without their flashing through his mind. A truth, or supposed truth, which is really the result of a very rapid inference, may seem to be apprehended intuitively. It has long been agreed by thinkers of the most opposite schools, that this mistake is actually made in so familiar an instance as that of the eyesight. There is nothing of which we appear to ourselves to be more directly conscious, than the distance of an object from us. Yet it has long been ascertained, that what is perceived by the eye, is at most nothing more than a variously coloured surface; that when we fancy we see distance, all we really see is certain variations of apparent size, and degrees of faintness of colour; and that our estimate of the object's distance from us is the result of a comparison (made with so much rapidity that we are unconscious of making it) between the size and colour of the object as they appear at the time, and the size and colour of the same or of similar objects as they appeared when close at hand, or when their degree of remoteness was known by other evidence. The perception of distance by the eye, which seems so like intuition, is thus, in reality, an inference grounded on experience; an inference, too, which we learn to make; and which we make with more and more correctness as our experience increases; though in familiar cases it takes place, so rapidly as to appear exactly on a par with those perceptions of sight which are really intuitive, our perceptions of colour.

Edwin Abbott Abbott photo

“The Art of Sight Recognition, being no longer needed, was no longer practised; and the studies of Geometry, Statics, Kinetics, and other kindred subjects, came soon to be considered superfluous, and fell into disrespect and neglect even at our University. The inferior Art of Feeling speedily experienced the same fate at our Elementary Schools….”

Source: Flatland: A Romance of Many Dimensions (1884), PART I: THIS WORLD, Chapter 9. Of the Universal Colour Bill
Context: The Art of Sight Recognition, being no longer needed, was no longer practised; and the studies of Geometry, Statics, Kinetics, and other kindred subjects, came soon to be considered superfluous, and fell into disrespect and neglect even at our University. The inferior Art of Feeling speedily experienced the same fate at our Elementary Schools.... Year by year the Soldiers and Artisans began more vehemently to assert — and with increasing truth — that there was no great difference between them and the very highest class of Polygons, now that they were raised to an equality with the latter, and enabled to grapple with all the difficulties and solve all the problems of life, whether Statical or Kinetical, by the simple process of Colour Recognition. Not content with the natural neglect into which Sight Recognition was falling, they began boldly to demand the legal prohibition of all "monopolizing and aristocratic Arts" and the consequent abolition of all endowments for the studies of Sight Recognition, Mathematics, and Feeling. Soon, they began to insist that inasmuch as Colour, which was a second Nature, had destroyed the need of aristocratic distinctions, the Law should follow in the same path, and that henceforth all individuals and all classes should be recognized as absolutely equal and entitled to equal rights.

“After Pythagoras, Anaxagoras the Clazomenian succeeded, who undertook many things pertaining to geometry. And Oenopides the Chian, was somewhat junior to Anaxagoras, and whom Plato mentions in his Rivals, as one who obtained mathematical glory. To these succeeded Hippocrates, the Chian, who invented the quadrature of the lunula, and Theodorus the Cyrenean, both of them eminent in geometrical knowledge. For the first of these, Hippocrates composed geometrical elements: but Plato, who was posterior to these, caused as well geometry itself, as the other mathematical disciplines, to receive a remarkable addition, on account of the great study he bestowed in their investigation. This he himself manifests, and his books, replete with mathematical discourses, evince: to which we may add, that he every where excites whatever in them is wonderful, and extends to philosophy. But in his time also lived Leodamas the Thasian, Architas the Tarentine, and Theætetus the Athenian; by whom theorems were increased, and advanced to a more skilful constitution. But Neoclides was junior to Leodamas, and his disciple was Leon; who added many things to those thought of by former geometricians. So that Leon also constructed elements more accurate, both on account of their multitude, and on account of the use which they exhibit: and besides this, he discovered a method of determining when a problem, whose investigation is sought for, is possible, and when it is impossible.”

Proclus (412–485) Greek philosopher

Source: The Philosophical and Mathematical Commentaries of Proclus on the First Book of Euclid's Elements Vol. 1 (1788), Ch. IV.

“She was no scholar in geometry or aught else, but she felt intuitively that the bend and slant of the way she went were somehow outside any other angles or bends she had ever known.”

C. L. Moore (1911–1987) American author

Black God's Kiss (1934)
Context: It was a long way down. Before she had gone very far the curious dizziness she had known before came over her again, a dizziness not entirely induced by the spirals she whirled around, but a deeper, atomic unsteadiness as if not only she but also the substances around her were shifting. There was something queer about the angles of those curves. She was no scholar in geometry or aught else, but she felt intuitively that the bend and slant of the way she went were somehow outside any other angles or bends she had ever known. They led into the unknown and the dark, but it seemed to her obscurely that they led into deeper darkness and mystery than the merely physical, as if, though she could not put it clearly even into thoughts, the peculiar and exact lines of the tunnel had been carefully angled to lead through poly-dimensional space as well as through the underground — perhaps through time, too.

Freeman Dyson photo

“A point has no existence by itself. It exists only as a part of the pattern of relationships which constitute the geometry of Euclid.”

Source: Infinite in All Directions (1988), Ch. 2 : Butterflies and Superstrings, p. 17
Context: Euclid... gave his famous definition of a point: "A point is that which has no parts, or which has no magnitude." …A point has no existence by itself. It exists only as a part of the pattern of relationships which constitute the geometry of Euclid. This is what one means when one says that a point is a mathematical abstraction. The question, What is a point? has no satisfactory answer. Euclid's definition certainly does not answer it. The right way to ask the question is: How does the concept of a point fit into the logical structure of Euclid's geometry?... It cannot be answered by a definition.

Baruch Spinoza photo

“He fell well short of mastering the art of demonstration; he had only a mediocre knowledge of analysis and geometry; what he knew best was to make lenses for microscopes.”

Baruch Spinoza (1632–1677) Dutch philosopher

Gottfried Wilhelm Leibniz, letter to Count Ernst von Hessen-Rheinfels (Aug. 14, 1683) in Gottfried Wilhelm Leibniz: Sämtliche Schriften und Briefe (1923-) II.ii. p. 535, as translated by Matthew Stewart, The Courtier and the Heretic (2006) pp. 228-229.
Context: Regarding Spinoza, whom M. Arnauld has called the most impious and most dangerous man of this century, he was truly an Atheist, [i. e., ] he allowed absolutely no Providence dispensing rewards and punishments according to justice.... The God he puts on parade is not like ours; he has no intellect or will.... He fell well short of mastering the art of demonstration; he had only a mediocre knowledge of analysis and geometry; what he knew best was to make lenses for microscopes.

Thomas Jefferson photo

“Well aware that the opinions and belief of men depend not on their own will, but follow involuntarily the evidence proposed to their minds; that Almighty God hath created the mind free, and manifested his supreme will that free it shall remain by making it altogether insusceptible of restraint; that all attempts to influence it by temporal punishments, or burthens, or by civil incapacitations, tend only to beget habits of hypocrisy and meanness, and are a departure from the plan of the holy author of our religion, who being lord both of body and mind, yet choose not to propagate it by coercions on either, as was in his Almighty power to do, but to exalt it by its influence on reason alone; that the impious presumption of legislature and ruler, civil as well as ecclesiastical, who, being themselves but fallible and uninspired men, have assumed dominion over the faith of others, setting up their own opinions and modes of thinking as the only true and infallible, and as such endeavoring to impose them on others, hath established and maintained false religions over the greatest part of the world and through all time: That to compel a man to furnish contributions of money for the propagation of opinions which he disbelieves and abhors, is sinful and tyrannical; … that our civil rights have no dependence on our religious opinions, any more than our opinions in physics or geometry; and therefore the proscribing any citizen as unworthy the public confidence by laying upon him an incapacity of being called to offices of trust or emolument, unless he profess or renounce this or that religions opinion, is depriving him injudiciously of those privileges and advantages to which, in common with his fellow-citizens, he has a natural right; that it tends also to corrupt the principles of that very religion it is meant to encourage, by bribing with a monopoly of worldly honours and emolumerits, those who will externally profess and conform to it; that though indeed these are criminals who do not withstand such temptation, yet neither are those innocent who lay the bait in their way; that the opinions of men are not the object of civil government, nor under its jurisdiction; that to suffer the civil magistrate to intrude his powers into the field of opinion and to restrain the profession or propagation of principles on supposition of their ill tendency is a dangerous fallacy, which at once destroys all religious liberty, … and finally, that truth is great and will prevail if left to herself; that she is the proper and sufficient antagonist to error, and has nothing to fear from the conflict unless by human interposition disarmed of her natural weapons, free argument and debate; errors ceasing to be dangerous when it is permitted freely to contradict them.”

Thomas Jefferson (1743–1826) 3rd President of the United States of America

A Bill for Establishing Religious Freedom, Chapter 82 (1779). Published in The Works of Thomas Jefferson in Twelve Volumes http://oll.libertyfund.org/ToC/0054.php, Federal Edition, Paul Leicester Ford, ed., New York: G. P. Putnam's Sons, 1904, Vol. 1 http://oll.libertyfund.org/Texts/Jefferson0136/Works/0054-01_Bk.pdf, pp. 438–441. Comparison of Jefferson's proposed draft and the bill enacted http://web.archive.org/web/19990128135214/http://www.geocities.com/Athens/7842/bill-act.htm
1770s

Ralph Waldo Emerson photo
Immanuel Kant photo

“Newton… (after having remarked that geometry only requires two of the mechanical actions which it postulates, namely, to describe a straight line and a circle) says: geometry is proud of being able to achieve so much while taking so little from extraneous sources. One might say of metaphysics, on the other hand: it stands astonished, that with so much offered it by pure mathematics it can effect so little.”

In the meantime, this little is something which mathematics indispensably requires in its application to natural science, which, inasmuch as it must here necessarily borrow from metaphysics, need not be ashamed to allow itself to be seen in company with the latter.
Preface, Tr. Bax (1883) citing Isaac Newton's Principia
Metaphysical Foundations of Natural Science (1786)

Immanuel Kant photo
Immanuel Kant photo
Immanuel Kant photo
Edmund Burke photo

“Civil freedom, gentlemen, is not, as many have endeavoured to persuade you, a thing that lies hid in the depth of abstruse science. It is a blessing and a benefit, not an abstract speculation; and all the just reasoning that can bo upon it, is of so coarse a texture, as perfectly to suit the ordinary capacities of those who are to enjoy, and of those who are to defend it. Far from any resemblance to those propositions in geometry and metaphysics, which admit no medium, but must be true or false in all their latitude; social and civil freedom, like all other things in common life, are variously mixed and modified, enjoyed in very different degrees, and shaped into an infinite diversity of forms, according to the temper and circumstances of every community. The extreme of liberty (which is its abstract perfection, but its real fault) obtains no where, nor ought to obtain any where. Because extremes, as we all know, in every point which relates either to our duties or satisfactions in life, are destructive both to virtue and enjoyment. Liberty too must be limited in order to be possessed. The degree of restraint it is impossible in any case to settle precisely. But it ought to be the constant aim of every wise public counsel, to find out by cautious experiments, and rational, cool endeavours, with how little, not how much of this restraint, the community can subsist. For liberty is a good to be improved, and not an evil to be lessened. It is not only a private blessing of the first order, but the vital spring and energy of the state itself, which has just so much life and vigour as there is liberty in it. But whether liberty be advantageous or not, (for I know it is a fashion to decry the very principle,) none will dispute that peace is a blessing; and peace must in the course of human affairs be frequently bought by some indulgence and toleration at least to liberty. For as the sabbath (though of divine institution) was made for man, not man for the sabbath, government, which can claim no higher origin or authority, in its exercise at least, ought to conform to the exigencies of the time, and the temper and character of the people, with whom it is concerned; and not always to attempt violently to bend the people to their theories of subjection. The bulk of mankind on their part are not excessively curious concerning any theories, whilst they are really happy; and one sure symptom of an ill-conducted state, is the propensity of the people to resort to them.”

Edmund Burke (1729–1797) Anglo-Irish statesman

Letter to the Sheriffs of Bristol (1777)

Swathi Thirunal Rama Varma photo
Ptolemy photo
Richard Feynman photo
David Hilbert photo
David Hilbert photo
John D. Carmack photo
David Hilbert photo
Gottlob Frege photo

“A philosopher who has no connection to geometry is only half a philosopher, and a mathematician who has no philosophical vein is only half a mathematician.”

Gottlob Frege (1848–1925) mathematician, logician, philosopher

Original: (de) Ein Philosoph, der keine Beziehung zur Geometrie hat, ist nur ein halber Philosoph, und ein Mathematiker, der keine philosophische Ader hat, ist nur ein halber Mathematiker.

Gottlob Frege: Erkenntnisquellen der Mathematik und der mathematischen Naturwissenschaften, 1924/1925, submitted to Wissenschaftliche Grundlagen; posthumously published in: Frege, Gottlob: Nachgelassene Schriften und Wissenschaftlicher Briefwechsel. Felix Meiner Verlag, 1990, p. 293