Isaac Newton(1643–1727)

Isaac Newton was born at Woolsthorpe Manor near Grantham in Lincolnshire on Christmas Day 1642 in the old English calendar, the fourth of January 1643 in the modern one, the posthumous son of a yeoman farmer who had died three months earlier and a mother who left him in the care of his grandmother soon after. He was sent to the King's School at Grantham at twelve, lodging with the apothecary Mr Clark, where he filled a notebook with mechanical drawings, sundials cut into the walls and a working windmill driven by a mouse on a treadwheel. He went up to Trinity College, Cambridge in June 1661, a subsizar paying his keep by waiting on wealthier students, took his Bachelor of Arts in 1665, and at that moment the university closed for the plague.

He went home to Woolsthorpe for eighteen months and did, in that time, the work of a century. The notebooks of 1665 and 1666 set out the method of fluxions, what we now call the differential and integral calculus; the decomposition of white light through a prism into the colours of the spectrum; and the first quantitative statement of the law of universal gravitation, prompted, by his own later account to William Stukeley, by the fall of an apple in the Woolsthorpe orchard. He came back to Cambridge in 1667, was elected a fellow of Trinity in the autumn, and in 1669 succeeded Isaac Barrow as Lucasian Professor of Mathematics at twenty-six.

In 1668 he built the first practical reflecting telescope, a six-inch instrument that solved the chromatic aberration of refractors by replacing the objective lens with a curved mirror; the Royal Society admitted him on the strength of it in 1672. His paper of the same year on the prismatic dispersion of light is the founding document of modern optics. But the work for which the world knows his name took shape between 1684 and 1687, prompted by a question from Edmond Halley about the orbits of comets. Newton answered with the Philosophiae Naturalis Principia Mathematica, the Mathematical Principles of Natural Philosophy, published in Latin in three books in July 1687 at Halley's expense.

The Principia derived from three laws of motion and one law of universal gravitation the orbits of the planets, the motion of the Moon, the precession of the equinoxes, the trajectories of comets and the shape of the Earth, and did it with a geometric rigour that withstood every test for two centuries. It is the single most consequential book ever published in the physical sciences. Newton followed it in 1704 with the Opticks, written in English and addressed to a wider audience, which carried his work on light and colour into the eighteenth-century reading public and shaped the experimental method of every laboratory that took it up.

In 1696 he left Cambridge for London to become Warden, and from 1700 Master, of the Royal Mint, where he reformed the coinage and prosecuted the great recoinage with an administrator's exactness. He was elected President of the Royal Society in 1703 and held the chair for the rest of his life; Queen Anne knighted him at Trinity in April 1705, the first man of science raised to a knighthood for his work. He died at Kensington on the thirty-first of March 1727 and was buried in Westminster Abbey beneath a monument that names him as the glory of the human race. The Newton name in modern science carries the weight of the framework on which every later physics was built.