Sir Isaac Newton

Galileo's Heir

Isaac Newton, English mathematician and physicist. English scientist and mathematician Isaac Newton's (1642-1727) discoveries were prolific and exerted a huge influence on science and thought.
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It was almost like handing over the reins from one astronomer to another. In 1642, in the space of just eleven months, astronomer Galileo Galilei died at Arcetri, near Florence, on January 8, 1642. More than nine hundred miles away, Hannah Newton gave birth to a premature baby boy on Christmas day in Lincolnshire, England. Named after his late father, Isaac (who died just three months shy of his son’s birth), the baby was quite small and not expected to live.

It was an inauspicious beginning for one of the great minds of math and science. 

Becoming Newton

Young Sir Isaac Newton did survive, and at the age of thirteen, he left to attend grammar school in Grantham. Taking up lodging with the local apothecary, he was fascinated by chemicals. His mother wanted him to become a farmer, but Newton had other ideas. His uncle was a clergyman who had studied at Cambridge. He persuaded his sister that Isaac should attend the university, so in 1661 the young man went to Trinity College, Cambridge. During his first three years, Isaac paid his tuition by waiting tables and cleaning rooms.

Eventually, he was honored by being elected a scholar, which guaranteed four years of financial support. Before he could benefit, however, the university closed in the summer of 1665 when the plague began its merciless spread across Europe. Returning home, Newton spent the next two years in self-study of astronomy, mathematics, and the applications of physics to astronomy, and spent his career developing his famous three laws of motion.

A legend of history has it that while sitting in his garden in Woolsthorpe in 1666, an apple fell on Newton's head, producing his theories of universal gravitation. While the story is popular, and certainly has charm, it is more likely that these ideas were the work of many years of study and thought.

He worked with Edmund Halley, who helped Newton publish his famous work, Principia Mathematica. Newton died in March 1626.

Sir Isaac Newton finally returned to Cambridge in 1667, where he spent the next 29 years. During this time, he published many of his most famous works, beginning with the treatise, "De Analysi," dealing with infinite series. Newton’s friend and mentor Isaac Barrow was responsible for bringing the work to the attention of the mathematics community. Shortly afterwards, Barrow who held the Lucasian Professorship (established just four years previously, with Barrow the only recipient) at Cambridge gave it up so that Newton could have the Chair.

With his name becoming well known in scientific circles, Sir Isaac Newton came to the attention of the public for his work in astronomy, when he designed and constructed the first reflecting telescope.

This breakthrough in telescope technology, which gave a sharper image than was possible with a large lens, ensured his election to membership in the Royal Society.

The scientists, Sir Christopher Wren, Robert Hooke, and Edmond Halley began a disagreement in 1684, over whether it was possible that the elliptical orbits of the planets could be caused by gravitational force towards the sun which varied inversely as the square of the distance. Halley traveled to Cambridge to ask the Lucasian Chair, himself.

Sir Isaac Newton claimed to have solved the problem four years earlier, but could not find the proof among his papers. After Halley’s departure, Isaac worked diligently on the problem and sent an improved version of the proof to the distinguished scientists in London. Throwing himself into the project of developing and expanding his theories, Newton eventually turned this work into his greatest book, “Philosophiae Naturalis Principia Mathematica” in 1686.

This work, which Halley encouraged him to write, and which Halley published at his own expense, brought him more into the view of the public and changed our view of the universe forever.

Shortly after this, Sir Isaac Newton moved to London, accepting the position of Master of the Mint. For many years afterward, he argued with Robert Hooke over who had actually discovered the connection between elliptical orbits and the inverse square law, a dispute which ended only with Hooke’s death in 1703.

In 1705, Queen Anne bestowed knighthood upon him, making him Sir Isaac Newton. Another dispute began in 1709, this time with German mathematician, Gottfried Leibniz, over which of them had invented calculus. While it may never have been settled to the satisfaction of either man, it lasted until around 1716.

One reason for Sir Isaac Newton's disputes with other scientists was his tendency to write his brilliant articles, then not publish until after another scientist created similar work. Besides his earlier work, "De Analysi" (which didn't see publication until 1711) and "Principia" (published in 1687), Newton's other works included "Optics" (published in 1704), "The Universal Arithmetic" (published in 1707), the "Lectiones Opticae" (published in 1729), the "Method of Fluxions" (published in 1736), and the "Geometrica Analytica" (printed in 1779).

On March 20, 1727, Sir Isaac Newton died near London. He was buried in Westminster Abbey, the first scientist to be accorded this honor. Today, Stephen Hawking holds the Lucasian Chair.