Thread by @mcnees

Physicist and mathematician Isaac Newton was born #OTD in 1643. He revolutionized our understanding of mathematics, mechanics, gravity, and optics, then foiled counterfeiters as warden of the Royal Mint.
Portrait: Barrington Bramley, after Godfrey Kneller

Newton's "Philosophiæ Naturalis Principia Mathematica” was published in 1687. It lays out his three Laws of Motion, which explain the relationship between the forces and changes in an object’s motion, and his universal law of gravitation.

You can page through Newton's own annotated copy of his Principia here, courtesy of the Cambridge University Library. (You can also download copies of individual pages.)
cudl.lib.cam.ac.uk/view/PR-ADV-B-…

[everyone take a few minutes to read the text and fully absorb it]

"After dinner, the weather being warm, we went into the garden and drank thea, under the shade of some apple trees."

Newton recounted the story of a falling apple to the writer William Stukeley, who included it in "The Memoirs of Sir Isaac Newton's Life."

The Royal Society has a copy of Stukeley’s “Memoirs of Sir Isaac Newton’s Life” that you can peruse online:
ttp.royalsociety.org//ttp/ttp.html?…

It has become very popular over the last few years (because of [sweeping arm gesture] all of this) to claim that Newton made incredible discoveries and advances while stuck at his mother’s country home during England’s bubonic “Great Plague” that began in 1665.

I mean, if Newton just needed some social distancing and a sweeping plague to discover gravity, surely you can take advantage of these Covid lockdowns to do something magnificent. Right?

No. That’s not how any of this happened.

https://twitter.com/neiltyson/status/1245111777270157318

Newton began his optics work in 1666 but it went on for years and he didn't present it to the Royal Society until 1672. He may have had the insight about Earth's gravity extending to the moon in 1666, but it took decades to really develop his universal law of gravitation. Also…

...he was living with his mother. All his needs were being taken care of. No kids, cleaning, laundry, or cooking.

So don't buy into these stories. I get the need for silver linings, but Newton didn’t do all this stuff in quarantine. Be kind to yourself.

(I wish @darth was out of hibernation to do a movie poster. Bradley Cooper is Sir Isaac Newton in “Silver Linings Principia.”)

(Also "lone genius with a comprehensive support network" is an outdated picture of scientific progress that doesn’t reflect how science gets done nowadays and isn't exactly a great parallel for what most of us are going through with Covid.)

Anyway, we all know about Newton's scientific accomplishments. What is lesser known is the fact that he served first as Warden and then Master of the Royal Mint for the last 30 years of his life, from 1696 to around 1727.

He took this position very seriously. During the Great Recoinage of 1696 he estimated that as much as 20% of the reclaimed currency was counterfeit. Newton took it upon himself to deal with the problem.

He had himself made a Justice of the Peace, and would go undercover –– sometimes in disguise! –– to collect evidence. Then, after the counterfeiters had been arrested, Sir Isaac Newton would often question them himself.

This is not exactly in keeping with the image of Sir Isaac Newton that most of us probably have. Apparently he liked to get his hands dirty!
royalmintmuseum.org.uk/journal/people…

Here is a little story about Newton which may or may not be related to his interest in the responsibilities of the Royal Mint. In 1688 the British Parliament repealed the "Act Against Multipliers."

This was a law that had been passed in 1404. It forbid alchemists from transmuting base metals into something more precious, like gold or silver. Makes sense –– you don't want alchemists devaluing your currency!

The law was repealed after lobbying by Robert Boyle, whose work at the time was laying the groundwork for modern chemistry.

Newton, who was obsessed with alchemy, hypothesized that the campaign to repeal the law meant that Boyle must have found an alchemical method for producing gold.

(This was not the case. You cannot chemically transmute an element! Indeed, all the gold you’ve ever seen or heard about was likely formed in supernovae or a collision between two neutron stars. Boyle did not have access to either of those.)

Anyway, Isaac Newton died #OTD in 1727. Here's a copy of his death mask. It was made in 1892 from the plaster originals.
Image: @NewtonInstitute, on loan from the Whipple Museum of Science

Sorry, forgot the dog. Isaac Newton supposedly told a friend that his dog Diamond helped him uncover two theorems. Also, there’s a story about Diamond being responsible for a fire that destroyed some of Newton’s papers.

Personally, as far as the fire is concerned, I think Diamond was framed.