"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 Mathematics See all quotes by Samuel Vince →

React to this quote

Resonant Thoughts

"If Walter Bagehot was right that “one of the greatest pains to human nature is the pain of a new idea,” Ken caused an extraordinary amount of pain. Both in his economic thinking and in his political a…"

— Amartya Sen

Economics1933

#politics

"Our life energies are the most basic and the most powerful aspect of human beings. Though most people are unaware of it, whichever way our energies play, that’s the way our bodies and our minds and ou…"

— Jaggi Vasudev

Music1957

#life

"I have since often observed, how incongruous and irrational the common temper of mankind is, especially of youth, to that reason which ought to guide them in such cases - viz. they are not ashamed to …"

— Daniel Defoe

Journalism1660–1731

#wisdom

"No kind action ever stopped with itself. Fecundity belongs to it in its own right. One kind action leads to another. By one we commit ourselves to more than one. Our example is followed. The single ac…"

— Frederick William Faber

Literature1814–1863

#leadership