Isaac Newton Quotes
Sir Isaac Newton was an English mathematician, physicist, astronomer, alchemist, and natural philosopher whose Mathematical Principles of Natural Philosophy laid the foundation for classical mechanics and helped to inaugurate modern science. His three laws of motion and the law of universal gravitation unified terrestrial and celestial physics in a single mathematical framework. The quotes below are attributed to Isaac Newton, organized by topic.
Browse Isaac Newton by topic
Isaac Newton on Justice
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“This is a variation on a much older adage, which Roger Bacon attributed to Aristotle : Amicus Plato sed magis amica veritas . Bacon was perhaps paraphrasing a statement in the Nicomachean Ethics : Where both are friends, it is right to prefer truth.”
Amicus Plato — amicus Aristoteles — magis amica veritas
Isaac Newton on Knowledge
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“If I have seen further it is by standing on the shoulders of giants.”
If I have seen further it is by standing on ye sholders of Giants . -
Attributed to Isaac Newton:
“I do not feign hypotheses.”
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Attributed to Isaac Newton:
“What we know is a drop, what we don't know is an ocean.”
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“Amicus Plato — amicus Aristoteles — magis amica veritas”
Plato is my friend — Aristotle is my friend — but my greatest friend is truth . | These are notes in Latin that Newton wrote to himself that he titled: Quaestiones Quaedam Philosophicae [Certain Philosophical Questions] (c. 1664) | Variant translations: Plato is my friend, Aristotle is my friend, but my best friend is truth. Plato is my friend — Aristotle is my friend — truth is a greater friend. -
“These are notes in Latin that Newton wrote to himself that he titled: Quaestiones Quaedam Philosophicae [Certain Philosophical Questions] (c. 1664)”
Amicus Plato — amicus Aristoteles — magis amica veritas -
“The best and safest method of philosophizing seems to be, first to enquire diligently into the properties of things, and to establish these properties by experiment, and then to proceed more slowly to hypothesis for the explanation of them. For hypotheses should be employed only in explaining the properties of things, but not assumed in determining them, unless so far as they may furnish experiments.”
Letter to Ignatius Pardies (1672) Philosophical Transactions of the Royal Society (Feb. 1671/2) as quoted by William L. Harper, Isaac Newton's Scientific Method: Turning Data Into Evidence about Gravity and Cosmology (2011) -
“The best and safest method of philosophizing seems to be, first to enquire diligently into the properties of things, and to establish these properties by experiment, and then to proceed more slowly to hypothesis for the explanation of them. For hypotheses should be employed only in explaining the properties of things, but not assumed in determining them, unless so far as they may furnish experimen”
Letter to Ignatius Pardies (1672) Philosophical Transactions of the Royal Society (Feb. 1671/2) as quoted by William L. Harper, Isaac Newton's Scientific Method: Turning Data Into Evidence about Gravity and Cosmology (2011) -
“1. Fidelity & Allegiance sworn to the King is only such a fidelity and obedience as is due to him by the law of the land; for were that faith and allegiance more than what the law requires, we would swear ourselves slaves , and the King absolute; whereas, by the law, we are free men, notwithstanding those Oaths. 2. When , therefore, the obligation by the law to fidelity and allegiance ceases, that”
Letter to Dr. Covel Feb. 21, (1688-9) Thirteen Letters from Sir Isaac Newton to J. Covel, D.D. (1848)
Isaac Newton on Mind
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Attributed to Isaac Newton:
“I can calculate the motion of heavenly bodies, but not the madness of people.”
Isaac Newton on Nature
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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.”
Letter to Robert Hooke (15 February 1676) [5 February 1676 ( O.S. )] -
“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.”
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
Isaac Newton on Truth
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“Plato is my friend, Aristotle is my friend, but my greatest friend is truth.”
Amicus Plato — amicus Aristoteles — magis amica veritas -
“Truth is ever to be found in simplicity, and not in the multiplicity and confusion of things.”
Cited in Rules for methodizing the Apocalypse , Rule 9, from a manuscript published in The Religion of Isaac Newton (1974) by Frank E. Manuel, p. 120, as quoted in Socinianism And Arminianism : Antitrinitarians, Calvinists, And Cultural Exchange in Seventeenth-Century Europe (2005) by Martin Mulsow, Jan Rohls, p. 273. | Variant: Truth is ever to be found in the simplicity, and not in the multiplic
Things actually not said by Isaac Newton
A number of widely-shared lines are circulated as Isaac Newton but are in fact from someone else. Did Isaac Newton say these? No. Each entry below pairs the line with the person who actually wrote it.
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Did Isaac Newton say this? No.
“Tact is the knack of making a point without making an enemy.”
This quote is commonly attributed to philosophers but its actual source is uncertain or unverified in the standard reference works. Wikiquote's note on this attribution: Actually a statement by American advertising executive and author Howard W. Newton (1903–1951); attributions to Isaac are relatively recent, those to Howard date at least to Sylva Vol. 1-3 (1945), p. 57 , where it is cited to an earlier publication in Redbook . | Variant: Tact is the art of making a
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Did Isaac Newton say this? No.
“Les hommes construisent trop de murs et pas assez de ponts.”
This quote is commonly attributed to philosophers but its actual source is uncertain or unverified in the standard reference works. Wikiquote's note on this attribution: Men build too many walls and not enough bridges. | This became widely attributed to Isaac Newton after Dominique Pire ascribed it to "the words of Newton" in his Nobel Lecture, 11 December 1958. Pire refers not to Isaac, but to Joseph Fort Newton , who is widely reported to have said "People are lon
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Did Isaac Newton say this? No.
“If I had stayed for other people to make my tools and things for me, I had never made anything.”
This first appears in the Isaac Newton : A Biography (1934), citing unpublished papers by John Conduitt reporting an anecdote of an occasion where Conduitt asked Newton where he obtained the tools to make his reflecting telescope. Newton is said to have laughed and replied, "If I had stayed for other people to make my tools and things for me I had never made anything of it." (Disputed.)
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Did Isaac Newton say this? No.
“Atheism is so senseless. When I look at the solar system, I see the earth at the right distance from the sun to receive the proper amounts of heat and light. This did not happen by chance.”
As quoted in Isaac Newton: Inventor, Scientist, and Teacher (1975) by John Hudson Tiner. "Atheism is so senseless" is a statement Newton made indeed in "A short Schem of the true Religion", but no source for the rest of this statement has been located prior to 1975. Part of this statement might originate as a summation of observations by Colin Maclaurin in his An Account of Sir Isaac Newton's Philosophical Discoveries (1750), Book III, Ch. 5 : "On the quantity of watter and density of the sun and planets" : "… the earth … those planets which are nearer the sun are found to be more dense, by which they are enabled to bear the greater heat of the sun. This is the result of our most subtle… (Disputed.)