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It is true, however, that seeing an apple dropping from a tree - presumably at a safer distance than sitting underneath the tree - was a factor in him pursuing that theory.
It's only a shame Newton has been dead now for 291 years, because I recently carried out my own gravity experiment which might have helped him check his calculations.
All right, a confession - it was an inadvertent experiment. But it did involve gravity and a piece of fruit.
"What a lovely morning," I thought to myself, meandering chirpily down Stuart St, taking in the myriad sights and gripping, in my left hand, two largish satsuma mandarins.
When I drew level with York Pl, and surveyed again the damage done to the front of the old King Edward Technical College wall by that runaway truck a few weeks ago, I clutched the mandarins ever more tightly, lest they slip from my control and hare off down the hill.
Which is exactly what one of them did, to my horror, as I hastened over the Smith St crossing. In a flash I had visions of it bouncing down the Stuart St centre-line, all the while picking up speed and rebounding ever higher, until it finally knocked Robbie Burns' head off and careered madly through the Octagon.
I collected it gratefully and walked on. The mandarin was a little worse for wear but, boy, was it easier to peel.
A couple of days ago I had the strangest phone call.
I picked up the receiver and all I could hear for about 10 seconds was a dog barking down the line. Finally, an elderly man with a shaky voice asked me if I was there.
I know we have hearing dogs. But I didn't know we have dogs that actually make the phone call for you.
It all makes sense now why cockney rhyming slang for phone is dog and bone.
They've been everywhere in recent weeks. I walked along Portsmouth Dr to Musselburgh one evening after work at sunset and got a mouthful, hairful and shirtful of them. I'm talking about clouds of aphids, gnats or midges, whatever you want to call them.
Lloyd Pearson, of Caversham, noticed the density of aphids when he was visiting Ranfurly at the end of last month.
Lloyd took several photos, including three of differing aphid densities on wheelie-bin lids.
"The difference in aphid density on the three wheelie bin lids may tell a story about recycling. Aphid excretions are apparently rich in sugar, so good use is made of their waste by other insects. Perhaps that is why they are attracted to the [yellow] recycling bin?
"The other photo shows the aphid density in the air. The camera to fence distance was about 4m. At a very rough guess, there were about 20 to 30 aphids per cubic metre.
"There will probably be an expert out there who will know more about these aphids.
"I don't know what they have been thriving on, although there are lucerne aphids, but there may now be other crops which encourage the aphids to thrive. From memory, there was nothing like this before about 15 to 20 years ago."
Thanks for getting in touch, Lloyd. Any experts out there with thoughts on the matter?
And on that rather itchy, scratchy, note, it's farewell for another week.