“John Philoponus (c. 490-570) of Alexandria… refuted Aristotle's theory that the velocities of falling bodies in a given medium are proportional to their weight, making the observation that "if one lets fall simultaneously from the same height two bodies differing greatly in weight, one will find that the ratio of the times of their motion does not correspond to the ratios of their weights, but the difference in time is a very small one." …He also criticized Aristotle's antiperistasis theory of projectile motion, which states that the air displaced by the object flows back to push it from behind. Instead Philoponus concluded that "some incorporeal kinetic power is imparted by the thrower to the object thrown" and that "if an arrow or a stone is projected by force in a void, the same will happen much more easily, nothing being necessary except the thrower."”

— John Freely

This is the famous "impetus theory," which was revived in medieval Islam and again in fourteenth century Europe, giving rise to the beginning of modern dynamics.
Source: Before Galileo, The Birth of Modern Science in Medieval Europe (2012), p. 8

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John Freely 8

American physicist 1926–2017

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“…suppose α without weight, but β possessing weight; and let α pass over space γδ, but β in the same time pass over a space γε,—for that which has weight will be carried through the larger space. If now the heavy body be divided in the proportion that space γε bears to γδ, … and if the whole is carried through the whole space γε, then it must be that a part in the same time would be carried through γδ…”

Aristotle (-384–-321 BC) Classical Greek philosopher, student of Plato and founder of Western philosophy

Book III Ch. II as quoted by Florian Cajori (1899), as Aristotle's explanation of why bodies fall quicker in exact proportion to their weight.
On the Heavens

“According to the Special Theory of Relativity, the velocity of a moving body is always less than the velocity of light. Since the energy of motion of a body depends on its inertial mass and its velocity, it follows that if the energy of a body is increased indefinitely by the continual application of a force, the inertial mass of the body must be increased too; for, if not, the velocity would ultimately increase indefinitely and exceed the velocity of light. Einstein found that, corresponding to any increase in the energy content of a body, there is an equivalent increase in its inertial mass. Mass and energy thus appeared to be different names for the same thing, the energy associated with a mass M being Mc2, where c is the velocity of light; and the mass M of a body moving with velocity v he found to be given by the following formulaM = \frac {m}{\sqrt{(1 - \frac {v^2}{c^2}}}</center”

Gerald James Whitrow (1912–2000) British mathematician

The Structure of the Universe: An Introduction to Cosmology (1949)

“Aristotle whilst he labours to refute the ideas of Plato, falls upon one himself: for his summum bonum, is a Chimera, and there is no such thing as his Felicity.”

Thomas Browne book Religio Medici

Section 15
Religio Medici (1643), Part II

“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

“From Aristophanes to Aristotle, the attack on the demagogues always falls back on the one central question: in whose interest does the the leader lead?”

Moses I. Finley (1912–1986) American historian

Source: Democracy Ancient And Modern (Second Edition) (1985), Chapter 2, Athenian Demagogues, p. 43

“One main challenge of this research is to properly enumerate the things that matter and then to assign them weights, weights that presumably varied with time and place.”

Bruce Gilley (1966) researcher

Source: The Case for Colonialism: A Response to My Critics, Page 17-18 https://www.researchgate.net/publication/352039835_The_Case_for_Colonialism_A_Response_to_My_Critics The case for colonialism, Gilley, 2017

“He learned to communicate with birds and discovered their conversation was fantastically boring. It was all to do with windspeed, wingspans, power-to-weight ratios and a fair bit about berries.”

Douglas Adams book So Long, and Thanks for All the Fish

Source: So Long, and Thanks for All the Fish

“I have also cleared the electromagnetic theory of light from all unwarrantable assumption, so that we may safely determine the velocity of light by measuring the attraction between bodies kept at a given difference of potential, the value of which is known in electromagnetic measure.”

James Clerk Maxwell (1831–1879) Scottish physicist

Letter to C. Hockin, Esq. (Sept 7, 1864) as quoted by Lewis Campbell, William Garnett, The Life of James Clerk Maxwell: With Selections from His Correspondence and Occasional Writings https://books.google.com/books?id=B7gEAAAAYAAJ (1884)

“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)

“Let us suppose that an explosion occurs on Mars, which is observed by an astronomer on earth, who records the instant when he sees the flash. If light travelled instantaneously with an infinite velocity, this instant would coincide with the time… recorded by the… observer on Mars. In this way a meaning could be attached automatically to absolute time and the simultaneity of events at different places; indeed, the classical theory is now regarded as the limiting form of Einstein's theory when the velocity of light becomes infinite. But as there is a mass of experimental evidence supporting the view that light takes a finite time to travel… the terrestrial observer must correct the time recorded on his watch. This correction… will depend on assumptions concerning the velocity of light and the measurement of distance. Thus the concept of a world-wide simultaneity ceases to be a primitive idea.”

Gerald James Whitrow (1912–2000) British mathematician

p, 125
The Structure of the Universe: An Introduction to Cosmology (1949)

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