Quotes about ratio

A collection of quotes on the topic of ratio, use, time, other.

Quotes about ratio

Fulton J. Sheen photo

“Anxiety increases in direct ratio and proportion as man departs from God.”

Fulton J. Sheen (1895–1979) Catholic bishop and television presenter

Source: Peace of Soul (1949), Ch. 2, p. 19

Douglas Adams photo
Isaac Newton photo

“Bullialdus wrote that all force respecting the Sun as its center & depending on matter must be reciprocally in a duplicate ratio of the distance from the center.”

Isaac Newton (1643–1727) British physicist and mathematician and founder of modern classical physics

Letter to Edmund Halley (June 20, 1686) quoted in I. Bernard Cohen and George E. Smith, ed.s, The Cambridge Companion to Newton (2002) p. 204

William Osler photo

“Common sense in matters medical is rare, and is usually in inverse ratio to the degree of education.”

William Osler (1849–1919) Canadian pathologist, physician, educator, bibliophile, historian, author, cofounder of Johns Hopkins Hospi…

"Teaching and Thinking" in The Montreal Medical Journal (1895).

Ronald Fisher photo

“In organisms of all kinds the young are launched upon their careers endowed with a certain amount of biological capital derived from their parents. This varies enormously in amount in different species, but, in all, there has been, before the offspring is able to lead an independent existence, a certain expenditure of nutriment in addition, almost universally, to some expenditure of time or activity, which the parents are induced by their instincts to make for the advantage of their young. Let us consider the reproductive value of these offspring at the moment when this parental expenditure on their behalf has just ceased. If we consider the aggregate of an entire generation of such offspring it is clear that the total reproductive value of the males in this group is exactly equal to the total value of all the females, because each sex must supply half the ancestry of all future generations of the species. From this it follows that the sex ratio will so adjust itself, under the influence of Natural Selection, that the total parental expenditure incurred in respect of children of each sex, shall be equal; for if this were not so and the total expenditure incurred in producing males, for instance, were less than the total expenditure incurred in producing females, then since the total reproductive value of the males is equal to that of the females, it would follow that those parents, the innate tendencies of which caused them to produce males in excess, would, for the same expenditure, produce a greater amount of reproductive value; and in consequence would be the progenitors of a larger fraction of future generations than would parents having a congenital bias towards the production of females. Selection would thus raise the sex-ratio until the expenditure upon males became equal to that upon females.”

On natural selection acting on sex ratio: Fisher's principle, Ch. 6, p. 141.
The Genetical Theory of Natural Selection (1930)

Edgar Allan Poe photo

“I need scarcely observe that a poem deserves its title only inasmuch as it excites, by elevating the soul. The value of the poem is in the ratio of this elevating excitement. But all excitements are, through a psychal necessity, transient.”

Edgar Allan Poe (1809–1849) American author, poet, editor and literary critic

The Poetic Principle (1850)
Context: I hold that a long poem does not exist. I maintain that the phrase, "a long poem," is simply a flat contradiction in terms.
I need scarcely observe that a poem deserves its title only inasmuch as it excites, by elevating the soul. The value of the poem is in the ratio of this elevating excitement. But all excitements are, through a psychal necessity, transient. That degree of excitement which would entitle a poem to be so called at all, cannot be sustained throughout a composition of any great length.

Thomas J. Sargent photo
Thomas De Quincey photo

“A promise is binding in the inverse ratio of the numbers to whom it is made.”

Appendix.
Confessions of an English Opium-Eater (1822-1856)

Archimedes photo
Bernhard Riemann photo
Adolf A. Berle photo
Jan Tinbergen photo
Terry Pratchett photo
Larry Niven photo

“For each human being there is an optimum ratio between change and stasis. Too little change, he grows bored. Too little stability, he panics and loses his ability to adapt.”

Flash Crowd, section 9, in Three Trips in Time and Space (1973), edited by Robert Silverberg, p. 74

Nikola Tesla photo
Vera Rubin photo
Arthur C. Clarke photo
Johannes Kepler photo

“Geometry has two great treasures: one is the Theorem of Phythagoras, the other the division of a line in extreme and mean ratio. The first we can compare to a mass of gold; the other we may call a precious jewel.”

As quoted by Karl Fink, Geschichte der Elementar-Mathematik (1890) translated as A Brief History of Mathematics https://books.google.com/books?id=3hkPAAAAIAAJ (1900, 1903) by Wooster Woodruff Beman, David Eugene Smith. Also see Carl Benjamin Boyer, A History of Mathematics (1968).
Mysterium Cosmographicum (1596)

Aristarchus of Samos photo

“Proposition 18. The earth is to the moon in a ratio greater than that which 1259712 has to 79507, but less than that which 216000 has to 6859.”

Aristarchus of Samos ancient Greek astronomer and mathematician

p, 125
On the Sizes and Distances of the Sun and the Moon (c. 250 BC)
Variant: Proposition 17. The diameter of the earth is to the diameter of the moon in a ratio greater than that which 108 has to 43, but less than that which 60 has to 19.

Aristarchus of Samos photo
E. W. Hobson photo

“The first period embraces the time between the first records of empirical determinations of the ratio of the circumference to the diameter of a circle until the invention of the Differential and Integral Calculus, in the middle of the seventeenth century. This period, in which the ideal of an exact construction was never entirely lost sight of, and was occasionally supposed to have been attained, was the geometrical period, in which the main activity consisted in the approximate determination of π by the calculation of the sides or the areas of regular polygons in- and circum-scribed to the circle. The theoretical groundwork of the method was the Greek method of Exhaustions. In the earlier part of the period the work of approximation was much hampered by the backward condition of arithmetic due to the fact that our present system of numerical notation had not yet been invented; but the closeness of the approximations obtained in spite of this great obstacle are truly surprising. In the later part of this first period methods were devised by which the approximations to the value of π were obtained which required only a fraction of the labour involved in the earlier calculations. At the end of the period the method was developed to so high a degree of perfection that no further advance could be hoped for on the lines laid down by the Greek Mathematicians; for further progress more powerful methods were required.”

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

Source: Squaring the Circle (1913), pp. 10-11

Eduardo Torroja photo
Oliver Goldsmith photo
Carl Sagan photo
Gerald James Whitrow photo
El Lissitsky photo

“Writing improves in direct ratio to the number of things we can keep out of it that shouldn't be there.”

William Zinsser (1922–2015) writer, editor, journalist, literary critic, professor

Source: On Writing Well (Fifth Edition, orig. pub. 1976), Chapter 3, Clutter, p. 13

Aristarchus of Samos photo

“Proposition 15. The diameter of the sun has, to the diameter of the earth a ratio greater than that which 19 has to 3, but less than that which 43 has to 6.”

Aristarchus of Samos ancient Greek astronomer and mathematician

p, 125
On the Sizes and Distances of the Sun and the Moon (c. 250 BC)
Variant: Proposition 10. The sun has to the moon a ratio greater than that which 5832 has to 1, but less than that which 8000 has to 1.

Francis Crick photo
Marshall McLuhan photo
Ernesto Grassi photo
Thomas Little Heath photo
Thomas Piketty photo
Thomas Robert Malthus photo

“Had population and food increased in the same ratio, it is probable that man might never have emerged from the savage state.”

Thomas Robert Malthus (1766–1834) British political economist

Source: An Essay on The Principle of Population (First Edition 1798, unrevised), Chapter XVIII, paragraph 11, lines 16-17

Samuel Butler photo

“People are lucky and unlucky not according to what they get absolutely, but according to the ratio between what they get and what they have been led to expect.”

Samuel Butler (1835–1902) novelist

Lucky and Unlucky
The Note-Books of Samuel Butler (1912), Part XIV - Higgledy-Piggledy

Max Weber photo
Marshall McLuhan photo

“Media, by altering the environment, evoke in us unique ratios of sense perception…When these ratios change, men change.”

Marshall McLuhan (1911–1980) Canadian educator, philosopher, and scholar-- a professor of English literature, a literary critic, and a …

1960s, The Medium is the Message (1967)

Donald A. Schön photo

“Belief in the stable state serves primarily to protect us from apprehension of the threats inherent in change. Belief in stability is a means of maintaining stability, or at any rate the illusion of stability. But the most threatening situations are those that confront us with uncertainty, and by ‘uncertainty’, I don’t mean risk, which is a probability ratio which we all know how to handle, particularly those who are managers of industry. We can deal with risk.”

Donald A. Schön (1930–1997) American academic

Donald Schon " REITH LECTURES 1970: Change and Industrial Society: Lecture 1: The Loss of the Stable State http://downloads.bbc.co.uk/rmhttp/radio4/transcripts/1970_reith1.pdf" at the BBC, 15 November 1970 – Radio 4; cited in: Richard Duane Carter (1981) Future challenges of management education. p. 102

Andrew Sega photo

“Music is nothing but ratios and harmonic math, anyways.”

Andrew Sega (1975) musician from America

Static Line interview, 1998

Émile Durkheim photo

“Solidarity can grow only in inverse ratio to personality.”

Émile Durkheim (1858–1917) French sociologist (1858-1917)

Source: The Division of Labor in Society (1893), p. 129 (in 1933 edition)

James Bolivar Manson photo

“Our visual discrimination is far better than our linguistic system at dealing with complex ratios and continuous variations in space, line, shape, and color.”

Jay Lemke (1946) American academic

Source: Textual politics: Discourse and social dynamics, 1995, p. 110

Andrew Sega photo
Augustus De Morgan photo
John Maynard Smith photo
Viktor Orbán photo
Samuel Vince photo

“I have lately spent some Thoughts relative to the Nature of Light, whether it be subject to the common Laws of Motion. In this particular Newton seems to contradict himself. For in his Principia Sect. 14th he applies the common Laws of Motion to account for Reflection and Refraction, as he does also in one Part of his Optics where he proves the Sine of Incid. to Sine Refr, in a given in a given Ratio. But in another Part he says, “nothing more is requisite for producing all the Variety of Colours and Degrees of Refrangibility than that the Rays of Light be Bodies of different Sizes, the least of which may make Violet, and the Greatest the Red"; this manifestly is not consistent with the Theory of Motion applied to Bodies, where the Magnitude of the Bodies is of no Consequence. Now it is evident that if the common Theory of Motion can be applied to Light, the Red Light must have had the greatest Velocity before Incidence, as it suffers the least Deviation, for if the Vels of all the Difft colour'd Light were equal before Incidence, they must by Newton's Principia Sect. Sect. 8. Prop. 1. have continued equal after, and therefore must have suffered the same Deviation. The Determination of this Point seems to be of considerable Importance, as we so often apply the Theory of Motion to Light.”

Samuel Vince (1749–1821) British mathematician, astronomer and physicist

As quoted in: Russell McCormmach (2011) Weighing the World: The Reverend John Michell of Thornhill. p. 193

Maurice Glasman, Baron Glasman photo
Thomas Robert Malthus photo

“Population, when unchecked, increases in a geometrical ratio, Subsistence, increases only in an arithmetical ratio.”

Thomas Robert Malthus (1766–1834) British political economist

Source: An Essay on The Principle of Population (First Edition 1798, unrevised), Chapter I, paragraph 18, lines 1-2

Archibald Hill photo

“In the last few years there has been a harvest of books and lectures about the "Mysterious Universe." The inconceivable magnitudes with which astronomy deals produce a sense of awe which lends itself to a poetic and philosophical treatment. "When I consider thy heavens, the work of thy hands, the moon and the starts, whuch thou hast ordained: what is man that thou art mindful of him? The literary skill with which this branch of science has been exploited compels one's admiration, but alos, a little, one's sense of the ridiculous. For other facts than those of astronomy, oother disciplines than of mathematics, can produce the same lively feelings of awe and reverence: the extraordinary finenness of their adjustments to the world outside: the amazing faculties of the human mind, of which we know neither whence it comes not whither it goes. In some fortunate people this reverence is produced by the natural bauty of a landscape, by the majesty of an ancient building, by the heroism of a rescue party, by poetry, or by music. God is doubtless a Mathematician, but he is also a Physiologist, an Engineer, a Mother, an Architect, a Coal Miner, a Poet, and a Gardener. Each of us views things in his own peculiar war, each clothes the Creator in a manner which fits into his own scheme. My God, for instance, among his other professions, is an Inventor: I picture him inventing water, carbon dioxide, and haemoglobin, crabs, frogs, and cuttle fish, whales and filterpassing organisms ( in the ratio of 100,000,000,000,000,000,000,000 to 1 in size), and rejoicing greatly over these weird and ingenious things, just as I rejoice greatly over some simple bit of apparatus. But I would nor urge that God is only an Inventor: for inventors are apt, as those who know them realize, to be very dull dogs. Indeed, I should be inclined rather to imagine God to be like a University, with all its teachers and professors together: not omittin the students, for he obviously possesses, judging from his inventions, that noblest human characteristic, a sense of humour.”

Archibald Hill (1886–1977) English physiologist and biophysicist

The Ethical Dilemma of Science and Other Writings https://books.google.com.mx/books?id=zaE1AAAAIAAJ&printsec=frontcover#v=onepage&q&f=false (1960, Cap 1. Scepticism and Faith, p. 41)

Aristarchus of Samos photo
Aristarchus of Samos photo
Max Frisch photo
Jeremy Rifkin photo
Brendan Brazier photo
Bernhard Riemann photo

“Let us imagine that from any given point the system of shortest lines going out from it is constructed; the position of an arbitrary point may then be determined by the initial direction of the geodesic in which it lies, and by its distance measured along that line from the origin. It can therefore be expressed in terms of the ratios dx0 of the quantities dx in this geodesic, and of the length s of this line. …the square of the line-element is \sum (dx)^2 for infinitesimal values of the x, but the term of next order in it is equal to a homogeneous function of the second order… an infinitesimal, therefore, of the fourth order; so that we obtain a finite quantity on dividing this by the square of the infinitesimal triangle, whose vertices are (0,0,0,…), (x1, x2, x3,…), (dx1, dx2, dx3,…). This quantity retains the same value so long as… the two geodesics from 0 to x and from 0 to dx remain in the same surface-element; it depends therefore only on place and direction. It is obviously zero when the manifold represented is flat, i. e., when the squared line-element is reducible to \sum (dx)^2, and may therefore be regarded as the measure of the deviation of the manifoldness from flatness at the given point in the given surface-direction. Multiplied by -¾ it becomes equal to the quantity which Privy Councillor Gauss has called the total curvature of a surface. …The measure-relations of a manifoldness in which the line-element is the square root of a quadric differential may be expressed in a manner wholly independent of the choice of independent variables. A method entirely similar may for this purpose be applied also to the manifoldness in which the line-element has a less simple expression, e. g., the fourth root of a quartic differential. In this case the line-element, generally speaking, is no longer reducible to the form of the square root of a sum of squares, and therefore the deviation from flatness in the squared line-element is an infinitesimal of the second order, while in those manifoldnesses it was of the fourth order. This property of the last-named continua may thus be called flatness of the smallest parts. The most important property of these continua for our present purpose, for whose sake alone they are here investigated, is that the relations of the twofold ones may be geometrically represented by surfaces, and of the morefold ones may be reduced to those of the surfaces included in them…”

Bernhard Riemann (1826–1866) German mathematician

On the Hypotheses which lie at the Bases of Geometry (1873)

Herbert Spencer photo

“What is essential to the idea of a slave? We primarily think of him as one who is owned by another. To be more than nominal, however, the ownership must be shown by control of the slave's actions — a control which is habitually for the benefit of the controller. That which fundamentally distinguishes the slave is that he labours under coercion to satisfy another's desires. The relation admits of sundry gradations. Remembering that originally the slave is a prisoner whose life is at the mercy of his captor, it suffices here to note that there is a harsh form of slavery in which, treated as an animal, he has to expend his entire effort for his owner's advantage. Under a system less harsh, though occupied chiefly in working for his owner, he is allowed a short time in which to work for himself, and some ground on which to grow extra food. A further amelioration gives him power to sell the produce of his plot and keep the proceeds. Then we come to the still more moderated form which commonly arises where, having been a free man working on his own land, conquest turns him into what we distinguish as a serf; and he has to give to his owner each year a fixed amount of labour or produce, or both: retaining the rest himself. Finally, in some cases, as in Russia before serfdom was abolished, he is allowed to leave his owner's estate and work or trade for himself elsewhere, under the condition that he shall pay an annual sum. What is it which, in these cases, leads us to qualify our conception of the slavery as more or less severe? Evidently the greater or smaller extent to which effort is compulsorily expended for the benefit of another instead of for self-benefit. If all the slave's labour is for his owner the slavery is heavy, and if but little it is light. Take now a further step. Suppose an owner dies, and his estate with its slaves comes into the hands of trustees; or suppose the estate and everything on it to be bought by a company; is the condition of the slave any the better if the amount of his compulsory labour remains the same? Suppose that for a company we substitute the community; does it make any difference to the slave if the time he has to work for others is as great, and the time left for himself is as small, as before? The essential question is—How much is he compelled to labour for other benefit than his own, and how much can he labour for his own benefit? The degree of his slavery varies according to the ratio between that which he is forced to yield up and that which he is allowed to retain; and it matters not whether his master is a single person or a society. If, without option, he has to labour for the society, and receives from the general stock such portion as the society awards him, he becomes a slave to the society.”

Herbert Spencer (1820–1903) English philosopher, biologist, sociologist, and prominent classical liberal political theorist

The Man versus the State (1884), The Coming Slavery

Joel Fuhrman photo
Mary Meeker photo
Nicole Oresme photo
Allan Kardec photo
Thomas Little Heath photo
Tori Amos photo

“Plato argued that in a good society the ratio of the richest to the poorest person's income should be at the most four to one.”

Harvey S. Rosen (1949) American economist

Source: Public Finance - International Edition - Sixth Edition, Chapter 7, Income Redistribution Conceptual Issues, p. 147

William Blake photo

“Reason, or the ratio of all we have already known, is not the same that it shall be when we know more.”

William Blake (1757–1827) English Romantic poet and artist

There Is No Natural Religion (1788)
1780s

Isaac Barrow photo
Vladimir Putin photo

“I think there are things of which I and the people who have worked with me can feel deservedly proud. They include restoring Russia's territorial integrity, strengthening the state, progress towards establishing a multiparty system, strengthening the parliamentary system, restoring the Armed Forces' potential and, of course, developing the economy. As you know, our economy has been growing by 6.9 percent a year on average over this time, and our GDP has increased by 7.7 percent over the first four months of this year alone.
When I began my work in the year 2000, 30 percent of our population was living below the poverty line. There has been a two-fold drop in the number of people living below the poverty line since then and the figure today is around 15 percent. By 2009-2010, we will bring this figure down to 10 percent, and this will bring us in line with the European average.
We had enormous debts, simply catastrophic for our economy, but we have paid them off in full now. Not only have we paid our debts, but we now have the best foreign debt to GDP ratio in Europe. Our gold and currency reserve figures are well known: in 2000, they stood at just $12 billion and we had a debt of more than 100 percent of GDP, but now we have the third-biggest gold and currency reserves in the world and they have increased by $90 billion over the first four months of this year alone.
During the 1990s and even in 2000-2001, we had massive capital flight from Russia with $15 billion, $20 billion or $25 billion leaving the country every year. Last year we reversed this situation for the first time and had capital inflow of $41 billion. We have already had capital inflow of $40 billion over the first four months of this year. Russia's stock market capitalisation showed immense growth last year and increased by more than 50 percent. This is one of the best results in the world, perhaps even the best. Our economy was near the bottom of the list of world economies in terms of size but today it has climbed to ninth place and in some areas has even overtaken some of the other G8 countries' economies. This means that today we are able to tackle social problems. Real incomes are growing by around 12 percent a year. Real income growth over the first four months of this year came to just over 18 percent, while wages rose by 11-12 percent.
Looking at the problems we have yet to resolve, one of the biggest is the huge income gap between the people at the top and the bottom of the scale. Combating poverty is obviously one of our top priorities in the immediate term and we still have to do a lot to improve our pension system too because the correlation between pensions and the average wage is still lower here than in Europe. The gap between incomes at the top and bottom end of the scale is still high here – a 15.6-15.7-fold difference. This is less than in the United States today (they have a figure of 15.9) but more than in the UK or Italy (where they have 13.6-13.7). But this remains a big gap for us and fighting poverty is one of our biggest priorities.”

Vladimir Putin (1952) President of Russia, former Prime Minister

When asked in June 2007 at the interview with G8 journalists about main achievements of his presidency http://web.archive.org/web/20070607221025/http://www.kremlin.ru/eng/speeches/2007/06/04/2149_type82916_132772.shtml.

Jesse Ventura photo
Thomas Piketty photo

“Infanticide and infant neglect exist in inverse ratio to the accessibility of abortion services.”

Sheri S. Tepper (1929–2016) American fiction writer

Source: Gibbon's Decline & Fall (1996), Chapter 10 (p. 173)

Aristarchus of Samos photo
Edgar Rice Burroughs photo
William Gibson photo
Willem de Sitter photo
Didier Sornette photo
Max Brooks photo
Marshall McLuhan photo

“Does the interiorization of media such as letters alter the ratio among our senses and change mental processes?”

Marshall McLuhan (1911–1980) Canadian educator, philosopher, and scholar-- a professor of English literature, a literary critic, and a …

Source: 1960s, The Gutenberg Galaxy (1962), p. 28

Shankar Dayal Sharma photo
Pierre Louis Maupertuis photo
Hendrik Lorentz photo

“One has been led to the conception of electrons, i. e. of extremely small particles, charged with electricity, which are present in immense numbers in all ponderable bodies, and by whose distribution and motions we endeavor to explain all electric and optical phenomena that are not confined to the free ether…. according to our modern views, the electrons in a conducting body, or at least a certain part of them, are supposed to be in a free state, so that they can obey an electric force by which the positive particles are driven in one, and the negative electrons in the opposite direction. In the case of a non-conducting substance, on the contrary, we shall assume that the electrons are bound to certain positions of equilibrium. If, in a metallic wire, the electrons of one kind, say the negative ones, are travelling in one direction, and perhaps those of the opposite kind in the opposite direction, we have to do with a current of conduction, such as may lead to a state in which a body connected to one end of the wire has an excess of either positive or negative electrons. This excess, the charge of the body as a whole, will, in the state of equilibrium and if the body consists of a conducting substance, be found in a very thin layer at its surface.
In a ponderable dielectric there can likewise be a motion of the electrons. Indeed, though we shall think of each of them as haying a definite position of equilibrium, we shall not suppose them to be wholly immovable. They can be displaced by an electric force exerted by the ether, which we conceive to penetrate all ponderable matter… the displacement will immediately give rise to a new force by which the particle is pulled back towards its original position, and which we may therefore appropriately distinguish by the name of elastic force. The motion of the electrons in non-conducting bodies, such as glass and sulphur, kept by the elastic force within certain bounds, together with the change of the dielectric displacement in the ether itself, now constitutes what Maxwell called the displacement current. A substance in which the electrons are shifted to new positions is said to be electrically polarized.
Again, under the influence of the elastic forces, the electrons can vibrate about their positions of equilibrium. In doing so, and perhaps also on account of other more irregular motions, they become the centres of waves that travel outwards in the surrounding ether and can be observed as light if the frequency is high enough. In this manner we can account for the emission of light and heat. As to the opposite phenomenon, that of absorption, this is explained by considering the vibrations that are communicated to the electrons by the periodic forces existing in an incident beam of light. If the motion of the electrons thus set vibrating does not go on undisturbed, but is converted in one way or another into the irregular agitation which we call heat, it is clear that part of the incident energy will be stored up in the body, in other terms [words] that there is a certain absorption. Nor is it the absorption alone that can be accounted for by a communication of motion to the electrons. This optical resonance, as it may in many cases be termed, can likewise make itself felt even if there is no resistance at all, so that the body is perfectly transparent. In this case also, the electrons contained within the molecules will be set in motion, and though no vibratory energy is lost, the oscillating particles will exert an influence on the velocity with which the vibrations are propagated through the body. By taking account of this reaction of the electrons we are enabled to establish an electromagnetic theory of the refrangibility of light, in its relation to the wave-length and the state of the matter, and to form a mental picture of the beautiful and varied phenomena of double refraction and circular polarization.
On the other hand, the theory of the motion of electrons in metallic bodies has been developed to a considerable extent…. important results that have been reached by Riecke, Drude and J. J. Thomson… the free electrons in these bodies partake of the heat-motion of the molecules of ordinary matter, travelling in all directions with such velocities that the mean kinetic energy of each of them is equal to that of a gaseous molecule at the same temperature. If we further suppose the electrons to strike over and over again against metallic atoms, so that they describe irregular zigzag-lines, we can make clear to ourselves the reason that metals are at the same time good conductors of heat and of electricity, and that, as a general rule, in the series of the metals, the two conductivities change in nearly the same ratio. The larger the number of free electrons, and the longer the time that elapses between two successive encounters, the greater will be the conductivity for heat as well as that for electricity.”

Hendrik Lorentz (1853–1928) Dutch physicist

Source: The Theory of Electrons and Its Applications to the Phenomena of Light and Radiant Heat (1916), Ch. I General principles. Theory of free electrons, pp. 8-10

George Boole photo
Gerald James Whitrow photo

“His days were full of meaningless ceremonies whose sacredness appeared to be in inverse ratio to their comprehensibility or usefulness.”

Mervyn Peake (1911–1968) English writer, artist, poet and illustrator

Source: Gormenghast (1950), Chapter 80 (p. 802)

Willem de Sitter photo

“Both the law of inertia and the law of gravitation contain a numerical factor or a constant belonging to matter, which is called mass. We have thus two definitions of mass; one by the law of inertia: mass is the ratio between force and acceleration. We may call the mass thus defined the inertial or passive mass, as it is a measure of the resistance offered by matter to a force acting on it. The second is defined by the law of gravitation, and might be called the gravitational or active mass, being a measure of the force exerted by one material body on another. The fact that these two constants or coefficients are the same is, in Newton's system, to be considered as a most remarkable accidental coincidence and was decidedly felt as such by Newton himself. He made experiments to determine the equality of the two masses by swinging a pendulum, of which the bob was hollow and could be filled up with different materials. The force acting on the pendulum is proportional to its active mass, its inertia is proportional to its passive mass, so that the period will depend on the ratio of the passive and the active mass. Consequently the fact that the period of all these different pendulums was the same, proves that this ratio is a constant, and can be made equal to unity by a suitable choice of units, i. e., the inertial and the gravitational mass are the same. These experiments have been repeated in the nineteenth century by Bessel, and in our own times by Eötvös and Zeeman, and the identity of the inertial and the gravitational mass is one of the best ascertained empirical facts in physics-perhaps the best. It follows that the so-called fictitious forces introduced by a motion of the body of reference, such as a rotation, are indistinguishable from real forces…. In Einstein's general theory of relativity there is also no formal theoretical difference, as there was in Newton's system…. the equality of inertial and gravitational mass is no longer an accidental coincidence, but a necessity.”

Willem de Sitter (1872–1934) Dutch cosmologist

p, 125
"The Astronomical Aspect of the Theory of Relativity" (1933)