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 Isaac
Newton Memorial
Newton, Sir Isaac (1642-1727), English
mathematician and physicist, considered one of the greatest scientists
in history, who made important contributions to many fields of science.
His discoveries and theories laid the foundation for much of the progress
in science since his time. Newton was one of the inventors of the branch
of mathematics called calculus (the other was German mathematician Gottfried
Wilhelm Leibniz). He also solved the mysteries of light and optics, formulated
the three laws of motion, and derived from them the law of universal gravitation.
See Gravitation; Mechanics.
Newton was born on December 25, 1642 (according to the Julian calendar
then in use; the date was January 4, 1643, according to the Gregorian calendar
in use today), at Woolsthorpe, near Grantham in Lincolnshire. When he was
three years old, his widowed mother remarried, leaving him in the care
of his grandmother. Eventually his mother, by then widowed a second time,
was persuaded to send him to grammar school in Grantham. Later, in the
summer of 1661, he was sent to Trinity College, at the University of Cambridge.
Newton received his bachelor's degree in 1665. After an intermission
of nearly two years to avoid the plague, Newton returned to Trinity, which
elected him to a fellowship in 1667. He received his master's degree in
1668. Newton ignored much of the established curriculum of the university
to pursue his own interests: mathematics and natural philosophy. Proceeding
entirely on his own, he investigated the latest developments in mathematics
and the new natural philosophy that treated nature as a complicated machine.
Almost immediately, he made fundamental discoveries that were instrumental
in his career in science.
The Fluxional Method
Newton's first achievement was in mathematics. He generalized the methods
that were being used to draw tangents to curves and to calculate the area
swept by curves, and he recognized that the two procedures were inverse
operations. By joining them in what he called the fluxional method, Newton
developed in the autumn of 1666 a kind of mathematics that is now known
as calculus. Calculus was a new and powerful method that carried modern
mathematics above the level of Greek geometry.
Although Newton was its inventor, he did not introduce calculus into
European mathematics. In 1675 Leibniz arrived independently at virtually
the same method, which he called differential calculus. Leibniz proceeded
to publish his method and received sole credit for its invention until
Newton published a detailed exposition of his fluxional method in 1704.
Always fearful of publication and criticism, Newton kept his discovery
to himself. However, enough was known of his abilities to effect his appointment
in 1669 as Lucasian Professor of Mathematics at the University of Cambridge.
Optics
Optics was another area of Newton's early interests. In trying to explain
how colors occur, he arrived at the idea that sunlight is a heterogeneous
blend of different rays-each of which represents a different color-and
that reflections and refractions cause colors to appear by separating the
blend into its components. Newton demonstrated his theory of colors by
passing a beam of sunlight through a type of prism, which split the beam
into separate colors.
In 1672 Newton sent a brief exposition of his theory of colors to the
Royal Society in London. Its appearance in the Royal Society's Philosophical
Transactions led to a number of criticisms that confirmed his fear of publication,
and he subsequently withdrew as much as possible into the solitude of his
Cambridge study. In 1704, however, Newton published Opticks, which explained
his theories in detail.
The Principia
In August 1684 Newton's solitude was interrupted by a visit from Edmund
Halley, the British astronomer and mathematician, who discussed with Newton
the problem of orbital motion. Newton had also pursued the science of mechanics
as an undergraduate, and at that time he had already entertained basic
notions about universal gravitation. As a result of Halley's visit, Newton
returned to these studies.
During the following two and a half years, Newton established the modern
science of dynamics by formulating his three laws of motion. Newton applied
these laws to Kepler's laws of orbital motion-formulated by the German
astronomer Johannes Kepler-and derived the law of universal gravitation.
Newton is probably best known for discovering universal gravitation, which
explains that all bodies in space and on earth are affected by the force
called gravity. He published this theory in his book Philosophiae Naturalis
Principia Mathematica in 1687. This book marked a turning point in the
history of science; it also ensured that its author could never regain
his privacy.
The Principia's appearance also involved Newton in an unpleasant episode
with the English philosopher and physicist Robert Hooke. In 1687 Hooke
claimed that Newton had stolen from him a central idea of the book: that
bodies attract each other with a force that varies inversely as the square
of their distance. However, most historians do not accept Hooke's charge
of plagiarism.
In the same year, 1687, Newton helped lead Cambridge's resistance to
the efforts of King James II to make the university a Catholic institution.
After the English Revolution in 1688, which drove James from England, the
university elected Newton one of its representatives in a special convening
of the country's parliament. The following four years were filled with
intense activity for Newton, as, buoyed by the triumph of the Principia,
he tried to put all his earlier achievements into a final written form.
In the summer of 1693 Newton showed symptoms of a severe emotional disorder.
Although he regained his health, his creative period had come to an end.
Newton's connections with the leaders of the new regime in England
led to his appointment as warden, and later master, of the Royal Mint in
London, where he lived after 1696. In 1703 the Royal Society elected him
president, an office he held for the rest of his life. As president, he
ordered the immediate publication of the astronomical observations of the
first Astronomer Royal of England, John Flamsteed. Newton needed these
observations to perfect his lunar theory. This matter led to a difficult
conflict with Flamsteed.
Newton also engaged in a violent dispute with Leibniz over priority
in the invention of calculus. Newton used his position as president of
the Royal Society to have a committee of that body investigate the question,
and he secretly wrote the committee's report, which charged Leibniz with
deliberate plagiarism. Newton also compiled the book of evidence that the
society published. The effects of the quarrel lingered nearly until his
death in 1727.
In addition to science, Newton also showed an interest in alchemy,
mysticism, and theology. Many pages of his notes and writings-particularly
from the later years of his career-are devoted to these topics. However,
historians have found little connection between these interests and Newton's
scientific work.
Contributed by:
Richard S. Westfall
"Newton, Sir Isaac," Microsoft(R) Encarta(R) 97 Encyclopedia. (c) 1993-1996
Microsoft Corporation. All rights reserved.
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