1675年出版的《解釋光屬性的假說》(An Hypothesis explaining the Properties of Light)中,牛頓認為粒子間力的傳遞是透過以太進行的。不過牛頓在與神智學家亨利·莫爾接觸後重新燃起了對鍊金術的興趣,並改用源於赫密斯神智學中粒子相吸互斥思想的神秘力量來解釋,替換了先前假設以太存在的看法。擁有許多牛頓鍊金術著作的經濟學大師約翰·梅納德·凱恩斯曾說:「牛頓不是理性時代的第一人,他是最後的一位鍊金術士。」[10]但牛頓對鍊金術的興趣卻與他對科學的貢獻息息相關[11],而且在那個時代鍊金術與科學也還沒有明確的區別。如果他沒有依靠神秘學思想來解釋穿過真空的超距作用,他可能也不會發展出他的重力理論。
同時代的作家威廉·斯蒂克利牧師在他的《艾薩克·牛頓爵士生平回憶錄》中記錄了1726年4月15日他在肯辛頓與牛頓的一次談話[39],在該次談話中,牛頓回憶了「從前,萬有引力的概念進入了他的腦海,由於蘋果的下落引起了他的思考,他心中想到,為什麼蘋果總會垂直地落在地上,為什麼不能向側邊或者向上移動,而是不斷地朝向地球的中心。」[40]相似的說法還出現在伏爾泰的著述《Essay on Epic Poetry》(1727)中:「艾薩克·牛頓爵士在他的花園裡散步,首次想到了他的重力體系,接著便看見一顆蘋果從樹上掉下。」[41]
《簡編年史》(Short Chronicle)、《世界之體系》(The System of the World)、《光學講稿》(Optical Lectures)、《古王國年表,修訂》(The Chronology of Ancient Kingdoms, Amended)和De mundi systemate在他死後的1728年出版。
《兩處著名聖經訛誤的歷史變遷》(An Historical Account of Two Notable Corruptions of Scripture,1754)
牛頓在世時,歐洲通行有兩種不同的曆法:在英國和西歐的部分地區仍使用儒略曆或稱「舊曆」,某些其他地方則已改用格里曆或稱「新曆」。在牛頓出生時,格里曆要比儒略曆快10天:因此牛頓出生於儒略曆1642年的聖誕節,或者是格里曆1643年的1月4日。此外,在1752年英國改用格里曆前,英格蘭新年開始於3月25日(道成肉身紀念日,the anniversary of the Incarnation)而不是1月1日,因此牛頓死亡時,儒略曆尚未跨年,但格里曆已跨年。除非另有說明,本文中其他的日期均採用儒略曆。
Cohen, I.B. Dictionary of Scientific Biography [科學傳記辭典]. 紐約: Charles Scribner's Sons. 1970: 11卷,43頁 (英語). Threatening my father and mother Smith to burn them and the house over them...
Bell, E.T. Men of Mathematics [大數學家] Touchstone edition. 紐約: Simon & Schuster. 1986: 91-2頁 [1937] (英語). Newton began his schooling in the village schools and was later sent to The King's School, Grantham, where he became the top student in the school. At King's, he lodged with the local apothecary, William Clarke and eventually became engaged to the apothecary's stepdaughter, Anne Storer, before he went off to the University of Cambridge at the age of 19. As Newton became engrossed in his studies, the romance cooled and Miss Storer married someone else. It is said he kept a warm memory of this love, but Newton had no other recorded 'sweet-hearts' and never married. 引文格式1維護:冗餘文本 (link)
Dobbs, J.T. Newton's Alchemy and His Theory of Matter. Isis. December 1982, 73 (4): p. 523. 引文格式1維護:冗餘文本 (link) quoting Opticks.原文為:「Are not gross Bodies and Light convertible into one another, ...and may not Bodies receive much of their Activity from the Particles of Light which enter their Composition?」
Keynes, John Maynard. Newton, The Man. The Collected Writings of John Maynard Keynes Volume X [凱恩斯作品集,卷X]. MacMillan St. Martin's Press. 1972: pp. 363–364 (英語). Newton was not the first of the age of reason: he was the last of the magicians. 引文格式1維護:冗餘文本 (link)
Westfall, Richard S. Never at Rest: A Biography of Isaac Newton [永不止息:艾薩克·牛頓傳]. 劍橋大學: 劍橋大學出版社. 1983: pp. 530–1 [1980] (英語). 引文格式1維護:冗餘文本 (link)提到了牛頓顯然拋棄了他的鍊金術研究。
原文為:「Nature and nature's laws lay hid in night; God said "Let Newton be" and all was light.」譯文取自:Koyré, Alexandre. 《牛顿研究》. 張卜天譯 第1版. 北京: 北京大學出版社. 2003年1月: 13. ISBN 7-301-06093-9(中文(簡體)).
Tiner, J.H. Isaac Newton: Inventor, Scientist and Teacher [艾薩克·牛頓:發明家、科學家和教師]. 美國密西根州米爾福德市: Mott Media. 1975 (英語). Gravity explains the motions of the planets, but it cannot explain who set the planets in motion. God governs all things and knows all that is or can be done.
Haakonssen, Knud. The Enlightenment, politics and providence: some Scottish and English comparisons. Martin Fitzpatrick ed. (編). Enlightenment and Religion: Rational Dissent in eighteenth-century Britain [啟蒙運動與宗教:十八世紀英國的理性異教者]. 劍橋: 劍橋大學出版社. : 64頁 (英語).
Principia, Book III; cited in; Newton’s Philosophy of Nature: Selections from his writings, p. 42, ed. H.S. Thayer, Hafner Library of Classics, NY, 1953.
A Short Scheme of the True Religion, manuscript quoted in Memoirs of the Life, Writings and Discoveries of Sir Isaac Newton by Sir David Brewster, Edinburgh, 1850; cited in; ibid, p. 65.
Marquard, Odo. "Burdened and Disemburdened Man and the Flight into Unindictability," in Farewell to Matters of Principle. Robert M. Wallace trans.倫敦:牛津大學出版社,1989。
Papers Show Isaac Newton's Religious Side, Predict Date of Apocalypse. The Associated Press. 2007-06-19 [2015-01-29]. (原始內容存檔於2007-06-29) (英語).原文為:「This I mention not to assert when the time of the end shall be, but to put a stop to the rash conjectures of fanciful men who are frequently predicting the time of the end, and by doing so bring the sacred prophesies into discredit as often as their predictions fail.」
Don Juan (1821), Canto 10, Verse I. In Jerome J. McGann (ed.), Lord Byron: The Complete Poetical Works (1986), Vol. 5, 437.「When Newton saw an apple fall, he found / In that slight startle from his contemplation -- / 'Tis said (for I'll not answer above ground / For any sage's creed or calculation) -- / A mode of proving that the earth turn'd round / In a most natural whirl, called "gravitation;" /
And this is the sole mortal who could grapple, / Since Adam, with a fall or with an apple.」
Conduitt, John. Keynes Ms. 130.4:Conduitt's account of Newton's life at Cambridge. Newtonproject. [2006-08-30]. (原始內容存檔於2006-10-04) (英語). In the year 1666 he retired again from Cambridge to his mother in Lincolnshire. Whilst he was pensively meandering in a garden it came into his thought that the power of gravity (which brought an apple from a tree to the ground) was not limited to a certain distance from earth, but that this power must extend much further than was usually thought. Why not as high as the Moon said he to himself & if so, that must influence her motion & perhaps retain her in her orbit, whereupon he fell a calculating what would be the effect of that supposition.
「when formerly, the notion of gravitation came into his mind. It was occasioned by the fall of an apple, as he sat in contemplative mood. Why should that apple always descend perpendicularly to the ground, thought he to himself. Why should it not go sideways or upwards, but constantly to the earth's centre.」
Wilson, Fred L. History of Science: Newton [科學史:牛頓]. Fred Wilson's Physics Web. [2015-01-29]. (原始內容存檔於2007-06-30) (英語). citing: Delambre, M. "Notice sur la vie et les ouvrages de M. le comte J. L. Lagrange," Oeuvres de Lagrange I. Paris, 1867, p. xx.原文為「the most fortunate, for we cannot find more than once a system of the world to establish.」
Memoirs of the Life, Writings, and Discoveries of Sir Isaac Newton (1855) by Sir David Brewster (Volume II. Ch. 27)。原文為「I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.」