Sir Isaac Newton PRS FRS (25 December 1642 – 20 March 1726) was an English mathematician, astronomer, theologian, author and physicist (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time, and a key figure in the scientific revolution. His book Philosophiæ Naturalis Principia Mathematica ("Mathematical Principles of Natural Philosophy"), first published in 1687, laid the foundations of classical mechanics. Newton also made pathbreaking contributions to optics, and he shares credit with Gottfried Wilhelm Leibniz for developing the infinitesimal calculus.

Portrait of Newton by Godfrey Kneller

HERE ARE NINE FACTS WE DON'T KNOW ABOUT THIS GREAT MAN

1.) His unhappy childhood helped shape his secretive personality
Newton was born prematurely on Christmas Day 1642 at his family’s home, Woolsthorpe Manor, near the town of Grantham, England, several months after the death of his father, an illiterate farmer. When Newton was three, his mother wed a wealthy clergyman, Barnabas Smith, who didn’t want a stepson.
Newton’s mother went to live with her new husband in another village, leaving behind her young son in the care of his grandparents.
The experience of being abandoned by his mother scarred Newton and likely played a role in shaping his solitary, untrusting nature.
As a teen, he made a list of his past sins and among them was: “Threatening my father and mother Smith to burn them and the house over them.”
As an adult, Newton immersed himself in his work, had no hobbies and never married. He even remained silent about some of his scientific and mathematical discoveries for years, if he published them at all.

2.) Newton’s mother wanted him to be a farmer:
At age 12, Newton was enrolled in a school in Grantham, where he boarded at the home of the local apothecary because the daily walk from Woolsthorpe Manor was too long. Initially, he wasn’t a strong student; however, as the story goes, following a confrontation with a school bully Newton started applying himself in an effort to best the other boy and transformed into a top student.
However, at age 15 or 16, he was ordered to quit school by his mother (then widowed for a second time) and return to Woolsthorpe Manor to become a farmer.
The teen was uninterested in the job and fared poorly at it. Eventually, Newton’s mother was persuaded by her son’s former headmaster in Grantham (where, incidentally, British Prime Minister Margaret Thatcher was born in 1925) to allow him to return to school. After finishing his coursework there, Newton left for Trinity College, University of Cambridge in 1661, putting farming behind him for good.

3.) The Black Death inadvertently set the stage for one of his most famous insights:
In 1665, following an outbreak of the bubonic plague in England, Cambridge University closed its doors, forcing Newton to return home to Woolsthorpe Manor. While sitting in the garden there one day, he saw an apple fall from a tree, providing him with the inspiration to eventually formulate his law of universal gravitation. Newton later relayed the apple story to William Stukeley, who included it in a book, “Memoir of Sir Isaac Newton’s Life,” published in 1752.
In 2010, a NASA astronaut carried a piece of the ancient apple tree aboard the space shuttle Atlantis for a mission to the International Space Station.
The Royal Society, a scientific organization once headed by Newton, loaned the piece of the tree for the voyage, as part of a celebration of the 350th anniversary of the group’s founding.
Today, the original apple tree continues to grow at Woolsthorpe Manor

4.) As a professor at Cambridge, his lectures were poorly attended:
In 1669, Newton, then 26, was appointed the Lucasian professor of mathematics at Cambridge, one of the world’s oldest universities, whose origins date to 1209. (Newton was the second person to hold the Lucasian professorship; the 17th person, from 1979 to 2009, was physicist and “A Brief History of Time” author Stephen Hawking.) Although he remained at Cambridge for nearly 30 years, Newton showed little interest in teaching or in his students, and his lectures were sparsely attended; frequently, no one showed up at all.
Newton’s attention was centered on his own research.

5.) Newton ran the Royal Mint and had forgers executed:
In 1696, Newton was named to the job of warden of the Royal Mint, which was responsible for producing England’s currency.
He left Cambridge, his long-time home, and moved to his nation’s capital city, where the mint was located in the Tower of London. Three years later, Newton was promoted to the more lucrative position of master of the mint, a post he held until his death in 1727.
During his tenure at the mint, Newton supervised a major initiative to take all of the country’s old coins out of circulation and replace them with more reliable currency. He also was focused on investigating counterfeiters, and as a result became acquainted with the city’s seedy underbelly as he personally tracked down and interviewed suspected criminals, receiving death threats along the way.
A number of forgers he went after were sent to the gallows.

6.) He had a serious interest in alchemy:
In addition to the scientific endeavors for which he’s best known, Newton spent much of his adult life pursuing another interest, alchemy, whose goals included finding the philosopher’s stone, a substance that allegedly could turn ordinary metals like lead and iron into gold.
He was secretive about his alchemical experiments and recorded some of his research in codes.
Among his other research projects, Newton analyzed the Bible in an attempt to find secret messages about how the universe works.

7.) Newton served in Parliament—quietly:
From 1689 to 1690, Newton was a member of Parliament, representing Cambridge University. During this time, the legislative body enacted the Bill of Rights, which limited the power of the monarchy and laid out the rights of Parliament along with certain individual rights.
Newton’s contributions to Parliament apparently were limited, though; he reportedly spoke only once, when he asked an usher to close a window because it was chilly. Nevertheless, while in London Newton became acquainted with a number of influential people, from King William III to the philosopher John Locke. Newton served a second brief term in Parliament, from 1701 to 1702, and again seems to have contributed little.

8.) He had fierce rivalries:
When it came to his intellectual rivals, Newton could be jealous and vindictive. Among those with whom he feuded was German mathematician and philosopher Gottfried Leibniz; the two men had a bitter battle over who invented calculus.
Newton developed a version of calculus in the 1660s but didn’t publish his work at the time. In the 1670s, Leibniz formulated his own version of calculus, publishing his work a decade later. Newton later charged that the German scholar had plagiarized his unpublished writings after documents summarizing it circulated through the Royal Society.
Leibniz contended he’d reached his results independently and implied that Newton had stolen from his published work. In an effort to defend himself, Leibniz eventually appealed to the Royal Society and in 1712 Newton, who’d served as the organization’s president since 1703, agreed that an impartial committee would be assembled to look into the issue.
Instead, he packed the committee with his supporters and even penned the group’s report, which publicly credited him with discovering calculus.
Today, however, Leibniz’s system of calculus is the one commonly used.

9.) Newton was knighted
In 1705, Newton was knighted by Queen Anne. By that time, he’d become wealthy after inheriting his mother’s property following her death in 1679 and also had published two major works, 1687’s “Mathematical Principles of Natural Philosophy” (commonly called the “Principia”) and 1704’s “Opticks.” After the celebrated scientist died at age 84 on March 20, 1727, he was buried in Westminster Abbey, the resting place of English monarchs as well as such notable non-royals as Charles Darwin, Charles Dickens and explorer David Livingstone
source: https://www.history.com/news/9-things-you-may-not-know-about-isaac-newton

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