Challenging Newton’s Apple
Recently The Royal Society put their copy of the best evidence in the world about the fabled story of Newton watching an apple fall up on the web. NPR picked up the story here.
Most Americans know the violent version of the story, where Newton actually gets hit on the head by the apple. This bit was 100% definitely a fabrication, added to the story more than 100 years after Newton’s death (likely by Isaac Disraeli).
But what about the actual event? Was Newton’s entire theory for gravity inspired by an apple? Mostly no. It’s a subject I researched heavily for chapter 1 of The Myths of Innovation. Newton was not famous for discovering gravity, but for writing the Principa Mathmatica, which explained, mathematically, how universal gravity functioned. It took him many years to write this book, despite the legend of his life centering on a singular moment of insight.
The primary evidence for the “apple event” is in a book The Royal Society posted titled Memoirs of Isaac Newton, written by his friend William Stukeley. But it’s a dubious record of facts:
- Stukeley was Newton’s admirer and interviewed Newton in 1726. Newton died in 1727.
- Stukeley published his ‘Memoirs of Newton’ in 1752 at earliest. Meaning Newton, and many of Newton’s contemporaries, never saw the book and confirmed its facts.
- Biographers, certainly in 1720, are not objective reporters checking facts. They are often fans of their subjects, as Stukeley was of Newton.
- At the time Stukeley and Newton talked they were sitting under apple trees.
- The ‘event’ Newton supposedly told Stukeley, happened 60 years earlier.
- There are few other first person sources anywhere, in Newton’s journals or other biographies, of ‘the event’. (Please comment if I’m wrong).
In James Glieck’s excellent biography, Isaac Newton, he strongly suggests Newton offered the story as an metaphoric anecdote, as way to express his curiosity about the world, rather than as a literal tale about specific singular moment that redefined his view of things.
Now my point is not to say epiphanies never happen. Instead it’s that they rarely eliminate the hard work and risk required to manifest the idea in the world. Even if Newton’s apple event took place as the legend described, Newton still worked for years to complete his theory on gravity. The moment did not spare him from years of effort to manifest the idea born from that moment.
Frankly I don’t trust Stukeley. He was apparently a good friend of Newton’s. Just as I wouldn’t trust a biographer/friend interviewing someone famous late in their life, who somehow manages to tell only them a story about something that happened decades ago, that the famous person never mentioned in any of their own extensive journals and writings or interviews with other people. I can guess Stukeley wanted Newton to look good. He also wanted his book to be read (though the publishing history of the memoir is unclear). And in the spirit of those two things some exaggeration of facts and conversion of abstract anecdotes into real specific events would not be surprising.
In an article at The Independent, one of the few pieces this week to do research at all, offers this report from an expert at the Royal Society, which owns the manuscript:
“Newton cleverly honed this anecdote over time,” said Keith Moore, head of archives at the Royal Society. “The story was certainly true, but let’s say it got better with the telling.” The story of the apple fit the idea of an Earth-shaped object being attracted to the Earth. It also had a resonance with the Biblical account of the tree of knowledge [only the word fruit is used in Genesis, but Western imagery has made the apple icon in the tale], and Newton was known to have extreme religious views, Mr Moore said.
I’m surprised that in the history of science so few people have raised any questions at all. I’d love to see the web help me round out the facts, find experts and other familiar with the sources. Spread the word.
Interesting thoughts. Thanks, Scott. There have been studies on the total failings of eyewitness accounts, and how memory on it’s own is about the worst memory strategy we have.
(I am inclined to point out to those who haven’t read Stukeley’s manuscript that he wrote Newton told him he was considering a falling apple when he started to wonder about the concept of why things fell inward. The ‘apple-on-the-head part’ was never brought up by Newton or Stukeley.)
You’re wrong about one thing. Epiphanies are the only true source of original human thought. You cannot systematically approach innovation. I’m sure that Newton had an epiphany with regard to the universal inverse square law he posited applied to gravity.
What’s most important about Newton’s no doubt fictitious apple is that it is popular science which is a fabulous combination.
Jan: I obviously disagree, as I wrote a whole book largely attempting to use evidence and researched history to show how epiphany is overstated in its value, and over-represented in actually stories of successful invention.
On what evidence is your claim based? What inventor’s journals or memoirs focus on the importance of epiphanies in their work? It’s often PR and journalists who emphasize these stories, or inventors interested in PR.
Another interesting thing is that Newton developed calculus to solve the problems of mechanics and gravitation, but when he published his theory of gravitation, he recast the proofs to use more conventional geometric arguments involving conics, and kept calculus jealously to himself. Newton was not above dissimulation and artifice.
Gottfried Leibniz independently reinvented calculus, but unlike Newton, he published it, leading to a century-long controversy over who really invented it.
I believe the verdict on calculus was that they invented it independently of each other, but Newton did it first (although as you say, he hadn’t shared it with the world).
Newton was very private about many of his studies, especially alchemy. Gleick’s biography is really fantastic and concise – I wish I had read that book before some of the others.
Some more tidbits here, although varying in certainty:
I think my final verdict is, I really don’t care if the apple event really happened.
I don’t think Newton had the kind of mind that needed an apple to suggest gravity. I suspect he had the kind of mind that wanted a dumbed down story to help explain the concept to mere mortals.
I’m not sure I care personally either. But I do care that the most popular referenced anecdote about discovery or brilliance among science writers has so little science or evidence behind it.
Hmmm… to what extent would dear Scott go to disprove a point. Tsk!
Had Stukeley’s biography gone online prior to the publication of his book… one wonders! :-)