Isaac Newton
Sir Isaac Newton FRS (25 December 1642 – 20 March 1726/27[a]) was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author who was described in his time as a natural philosopher.[7] He was a key figure in the Scientific Revolution and the Enlightenment that followed. His pioneering book Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), first published in 1687, consolidated many previous results and established classical mechanics.[8][9] Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus, though he developed calculus years before Leibniz.[10][11]
For other uses, see Isaac Newton (disambiguation).
Isaac Newton
4 January 1643 [O.S. 25 December 1642][a]
31 March 1727 (aged 84) [O.S. 20 March 1726][a]
Trinity College, Cambridge (B.A., 1665; M.A., 1668)[5]
- Newtonian mechanics
- universal gravitation
- calculus
- Newton's laws of motion
- optics
- binomial series
- Principia
- Newton's method
- Newton's law of cooling
- Newton's identities
- Newton's metal
- Newton line
- Newton–Gauss line
- Newtonian fluid
- Newton's rings
- Standing on the shoulders of giants
- List of all other works and concepts
- FRS (1672)[1]
- Knight Bachelor (1705)
- Physics
- natural philosophy
- alchemy
- theology
- mathematics
- astronomy
- economics
In the Principia, Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for tides, the trajectories of comets, the precession of the equinoxes and other phenomena, eradicating doubt about the Solar System's heliocentricity.[12] He demonstrated that the motion of objects on Earth and celestial bodies could be accounted for by the same principles. Newton's inference that the Earth is an oblate spheroid was later confirmed by the geodetic measurements of Maupertuis, La Condamine, and others, convincing most European scientists of the superiority of Newtonian mechanics over earlier systems.
Newton built the first practical reflecting telescope and developed a sophisticated theory of colour based on the observation that a prism separates white light into the colours of the visible spectrum. His work on light was collected in his highly influential book Opticks, published in 1704. He also formulated an empirical law of cooling, made the first theoretical calculation of the speed of sound, and introduced the notion of a Newtonian fluid. In addition to his work on calculus, as a mathematician Newton contributed to the study of power series, generalised the binomial theorem to non-integer exponents, developed a method for approximating the roots of a function, and classified most of the cubic plane curves.
Newton was a fellow of Trinity College and the second Lucasian Professor of Mathematics at the University of Cambridge. He was a devout but unorthodox Christian who privately rejected the doctrine of the Trinity. He refused to take holy orders in the Church of England, unlike most members of the Cambridge faculty of the day. Beyond his work on the mathematical sciences, Newton dedicated much of his time to the study of alchemy and biblical chronology, but most of his work in those areas remained unpublished until long after his death. Politically and personally tied to the Whig party, Newton served two brief terms as Member of Parliament for the University of Cambridge, in 1689–1690 and 1701–1702. He was knighted by Queen Anne in 1705 and spent the last three decades of his life in London, serving as Warden (1696–1699) and Master (1699–1727) of the Royal Mint, as well as president of the Royal Society (1703–1727).
Mid-life
Calculus
Newton's work has been said "to distinctly advance every branch of mathematics then studied".[32] His work on the subject, usually referred to as fluxions or calculus, seen in a manuscript of October 1666, is now published among Newton's mathematical papers.[33] His work De analysi per aequationes numero terminorum infinitas, sent by Isaac Barrow to John Collins in June 1669, was identified by Barrow in a letter sent to Collins that August as the work "of an extraordinary genius and proficiency in these things".[34] Newton later became involved in a dispute with Leibniz over priority in the development of calculus. Most modern historians believe that Newton and Leibniz developed calculus independently, although with very different mathematical notations. However, it is established that Newton came to develop calculus much earlier than Leibniz.[10][11][35] Leibniz's notation and "differential Method", nowadays recognised as much more convenient notations, were adopted by continental European mathematicians, and after 1820 or so, also by British mathematicians.
His work extensively uses calculus in geometric form based on limiting values of the ratios of vanishingly small quantities: in the Principia itself, Newton gave demonstration of this under the name of "the method of first and last ratios"[36] and explained why he put his expositions in this form,[37] remarking also that "hereby the same thing is performed as by the method of indivisibles."[38] Because of this, the Principia has been called "a book dense with the theory and application of the infinitesimal calculus" in modern times[39] and in Newton's time "nearly all of it is of this calculus."[40] His use of methods involving "one or more orders of the infinitesimally small" is present in his De motu corporum in gyrum of 1684[41] and in his papers on motion "during the two decades preceding 1684".[42]
Personality
Although it was claimed that he was once engaged,[b] Newton never married. The French writer and philosopher Voltaire, who was in London at the time of Newton's funeral, said that he "was never sensible to any passion, was not subject to the common frailties of mankind, nor had any commerce with women—a circumstance which was assured me by the physician and surgeon who attended him in his last moments.”[112] There exists a widespread belief that Newton died a virgin, and writers as diverse as mathematician Charles Hutton,[113] economist John Maynard Keynes,[114] and physicist Carl Sagan have commented on it.[115]
Newton had a close friendship with the Swiss mathematician Nicolas Fatio de Duillier, whom he met in London around 1689[79]—some of their correspondence has survived.[116][117] Their relationship came to an abrupt and unexplained end in 1693, and at the same time Newton suffered a nervous breakdown,[118] which included sending wild accusatory letters to his friends Samuel Pepys and John Locke. His note to the latter included the charge that Locke had endeavoured to "embroil" him with "woemen & by other means".[119]
Newton was relatively modest about his achievements, writing in a letter to Robert Hooke in February 1676, "If I have seen further it is by standing on the shoulders of giants."[120] Two writers think that the sentence, written at a time when Newton and Hooke were in dispute over optical discoveries, was an oblique attack on Hooke (said to have been short and hunchbacked), rather than—or in addition to—a statement of modesty.[121][122] On the other hand, the widely known proverb about standing on the shoulders of giants, published among others by seventeenth-century poet George Herbert (a former orator of the University of Cambridge and fellow of Trinity College) in his Jacula Prudentum (1651), had as its main point that "a dwarf on a giant's shoulders sees farther of the two", and so its effect as an analogy would place Newton himself rather than Hooke as the 'dwarf'.
In a later memoir, Newton wrote, "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."[123]
The Enlightenment
Enlightenment philosophers chose a short history of scientific predecessors—Galileo, Boyle, and Newton principally—as the guides and guarantors of their applications of the singular concept of nature and natural law to every physical and social field of the day. In this respect, the lessons of history and the social structures built upon it could be discarded.[182]
It is held by European philosophers of the Enlightenment and by historians of the Enlightenment that Newton's publication of the Principia was a turning point in the Scientific Revolution and started the Enlightenment. It was Newton's conception of the universe based upon natural and rationally understandable laws that became one of the seeds for Enlightenment ideology.[183] Locke and Voltaire applied concepts of natural law to political systems advocating intrinsic rights; the physiocrats and Adam Smith applied natural conceptions of psychology and self-interest to economic systems; and sociologists criticised the current social order for trying to fit history into natural models of progress. Monboddo and Samuel Clarke resisted elements of Newton's work, but eventually rationalised it to conform with their strong religious views of nature.