The Fall of An Apple
Newton’s eureka moment, truth or myth?
Many scientists have achieved the honor of having their name attached to a scientific theory. Some have units of measurement named after them.
But only a few scientists have transcended even this level of greatness.
They have stories told about them.
Pythagoras is said to have understood musical scales as he walked past the sounds of blacksmiths striking hammers in unison.
Archimedes ran out on the streets naked, screaming “Eureka!” after he discovered the Archimedes principle in a bathtub.
The story of Galileo sitting in a church pondering on the nature of pendulum swings by comparing it to his pulse rate has been retold many times.
All of these events, however, are thought to be myths.
They may have been exaggerated versions or they may have not happened at all. There’s a small chance that these events actually took place. We will never be able to verify them. Regardless, these stories have firmly attached themselves to history.
And then there’s the story of the apple that fell on Isaac Newton’s head.
Though it has gained scientific folk tale status over the years, this one could be true, at least partially.
The legend has linked apples to gravity forever, but where did it come from?
In 1665, the University of Cambridge shut down and sent its students back home due to the breakout of the Great plague.
Isaac Newton returned to Woolsthorpe Manor, his birth home. He wouldn’t return to Cambridge until 1667. During these years he continued working on developing a theory of gravity among other things. All the accounts of the apple story reference this time.
It appeared in print for the first time in the year 1727 following his death.
In his “Essay on Epic Poetry”, philosopher Voltaire writes:
“And thus in
our Days Sir Isaak Newton walking in his Gardens had the first
Thought of his System of Gravitation, upon seeing an Apple
falling from a Tree"
Curiously enough, the line right before this references Pythagoras’s discovery of musical scales.
In the same year, another account was given by philosopher Robert Greene. He writes:
“ .. this celebrated theory has its origins like all of our knowledge, it is said, from the apple.”
Robert Greene notes that he heard the story from Martin Folkes, who served as vice president of the Royal society during the time Newton was president. Voltaire on other hand got his information from Newton’s niece Catherine Barton.
Catherine Barton’s husband John Conduitt also wrote about Isaac Newton and made note of the apple. His account confirms the time frame being the period he returned from Cambridge due to the plague.
The most cited version comes from William Stukelely’s biography of Isaac Newton. In it, he writes that the two of them had gone into the garden and drank tea under the shade of apple trees. He continues:
“amidst other discourse, he told me, he was just in the same situation, as when formerly, the notion of gravitation came into his mind. "why should that apple always descend perpendicularly to the ground," thought he to him self: occasion’d by the fall of an apple, as he sat in a comtemplative mood..”
It should be noted that all of these accounts are consistent with each other. As it is clear from William Stukeley’s version, Newton is said to have wondered about the way the apple fell.
He questioned why the apple always fell towards the center of the earth. Why didn’t it fly upwards or sideways he wondered.
In the handwritten version of John Conduitt’s account, he also gives a similar description of the questions that arose due to the falling apple.
Isaac Newton is said to have told this story many times over the years, well into his old age. All the independent sources mentioned so far would have likely heard it from the man himself.
So how did it change to the version we all have heard?
The first appearance of this change comes from Isaac D’Israeli who, in his book Curiosities of literature, wrote:
“Newton is indebted for many of his great discoveries; an apple falls upon him in his orchard,—and the system of attraction succeeds in his mind!”
This book was published in 1791, almost 70 years after Isaac Newton’s death. It is hard to tell if the story changed before or after this account.
In any case, the slightly more comical version of the story where the apple struck him on the head is what stuck.
Newton’s first biographer J.D Brewster tried to verify the authenticity of the story. He visited Woolsthorpe Manor in 1830 and claims to have taken a piece of one of the roots from the tree that was being preserved by the family that bought the property from the Newtons.
It is clear that around the time of Newton’s death and even much later, a tree was being identified as the apple tree. And just like J.D Brewster, others ended up with pieces and grafts that would be used to grow the tree in other places.
Today, the rare Flower of Kent tree descendants exist around the world. Seeds from the apple tree have even been sent to the International Space Station.
Biographers and other investigators have tried to establish the truth by using written accounts, sketches of Newton’s home and even going to the extent of performing radiocarbon dating and genetic fingerprinting on the trees.
These investigations can’t be used to say with absolute certainty that the story is true, but most conclude that it isn’t too far-fetched to dismiss it as false.
It would be easy to dismiss the tale as apocryphal but we would be missing the point.
Isaac Newton remains one of the greatest scientists of all time. He made significant contributions to physics that are relevant to this day.
The apple story isn’t just a romanticized tale about an important discovery. It is an example of how great figures of history get mythicized.
Not all of us can make sense of the laws of gravitation but we can conceptualize gravity by contemplating the fall of an apple. Perhaps that is the reason Isaac Newton himself told the story.
It may not then be relevant to wonder if the story was the truth or if it was a myth. But the case may be that the story was the truth that turned into a myth.
References for further reading -
