The most valuable and enduring lesson in art appreciation Michael Frith learnt at Warwick Academy wasn’t taught to him in a classroom.

Rather it was inadvertently stamped on his subconscious while standing in front of the school flagpole every morning in the late 1940s before classes even began.

In a whimsical essay he recently wrote for London’s Royal Academy of Arts, the celebrated Bermudian illustrator/designer/writer and former creative director of The Muppets said the school’s daily flag-raising ritual instilled in him an intuitive understanding of the critical roles of composition, symmetry and balance in painting.

“Every school day morning, here in Bermuda at Warwick Academy before the opening bell, we six-year-olds in our khaki shorts, neatly knotted neckties, oversized blazers (‘you’ll grow into it’) and knee socks sagging just so, assembled in the schoolyard, sang God Save the King (yes, children, there was a king once) and saluted as hand over hand the doughty maths mistress glided the Jack up the flagpole,” he said.

“Horizontal, vertical, two diagonals, all intersecting in the centre: was ever there a better, stronger, purer graphic than that flag? I was imprinted.

“But then, it was generally acknowledged I was a child of peculiar bent.”

Flash forward a dozen or so years. Michael Frith was now a student at Harvard majoring in art history. His talent for cartooning and caricatures — first pursued at Warwick because “if one wasn’t interested in football or cricket, [sketching outlandish drawings of teachers] was one way to gain at least a little respect from one’s classmates” — had also led him to the editor’s position at the college humour magazine, the redoubtable Harvard Lampoon.

He admits to throwing himself into this extracurricular activity with more energy than he devoted to his studies.

“I was taking art history partly because it was a ‘gut’ course, something I could slide through whilst I focused on the thing that really mattered — the magazine,” he said. “But — hey! — I drew pictures, loved looking at pictures, and out where I came from in the middle of the ocean? Other than my comic book collection, not much by way of pictures to look at. So [the course work] was all pretty revelatory.”

Perhaps the most electrifying revelation he experienced was one which confirmed and broadened his instinctive understanding of the importance of symmetry and balance in the visual arts. When a lecturer introduced him to the principles of composition in Renaissance Dutch painting, Frith had an epiphany in the shape of the Union Jack.

He realised it was as if a transparent flag had been overlaid on the canvases like a grid while the painters worked so “this bit related to that bit, this shape mirrored that shape, this empty section here perfectly balanced that chock-a-block section there, And under it all — the whole thing was held together by a Union Jack. I could have cried.

“I soon determined that there WAS NOT A DECENT PICTURE EVER, EVER PAINTED that didn’t stand up to that simple test of its composition: horizontal, vertical, two diagonals, all intersecting in the centre, each section in intense, ecstatic conversation with the other.”

For Frith “great paintings suddenly became at once both more understandable and more mysterious” by applying what he privately came to term “The Jack Test”.

Flash forward another 20-odd years when The Muppets had become a global phenomenon. Frith was by then in-house art director for Jim Henson’s freewheeling, sometimes subversive menagerie of furred, fleeced and feathered foam-rubber creations.

At the time the demand for Muppets merchandise was seemingly insatiable.

So he received the go-ahead for a pet project he had been quietly nurturing for some time, a book of Muppet-ised take-offs of works by the Great Masters supposedly from the collection of the pampered and egotistical Miss Piggy. The 1984 publication was titled Miss Piggy’s Treasury of Art Masterpieces from the Kermitage Collection, a punning reference to Russia’s Hermitage museum.

“The aim was to take a number of iconic pieces of Western art that would either be somewhat familiar to a general audience or would be readily recognisable as the work of some well-known artist — and substitute members of our troupe for the original subjects,” he said. “The pieces chosen would need to work on several levels: there should be some reason Piggy would have them in her collection; they should bring a smile to the viewer; and they should be ones that, for various reasons, had given me joy. Parodies? Not altogether. Tributes, really.”

And as tributes they had to pass Frith’s own “Jack Test” — particularly the planned burlesque of Grant Wood’s American Gothic with Miss Piggy herself and Kermit the Frog standing in for the pitchfork-holding Midwestern farmer and his spinster daughter in the 1930 original.

For Frith, American Gothic is an undisputed masterwork, a homage to the extraordinarily rigorous composition of the northern European painters whose works sealed Grant Wood’s understanding of the concepts of symmetry and balance — just as they had his own.

“Each shape mirrors and anticipates every other; the key elements, head, pitchfork, head, window, head, create an almost vertiginous rotating circle around the centre point; the two triangles of the roof lines, if continued down through the two faces, precisely divide them in equal ways; the shapes of the pitchfork, the stitching on the overall’s bib, the window are all joined in an elegant, almost erotic dance … one could go on for ever. And I’m sure someone will,” said Frith. “This was Wood’s passionate tribute to his [heroes], those [Dutch] Gothic masters. And I was determined to do the same for him.

“But, you know, with a frog and a pig.”

Shot in the Muppet team’s in-house photographic studio using painstakingly crafted sets and costumes based on those in the painting, the finished photo delighted devotees of Jim Henson and Grant Wood when it appeared in the Kermitage book. Everyone was delighted except, alas, the man who created it.

“I fear I — I! — failed the Jack Test,” said Frith.” Oh, it’s close! But when you draw those unforgiving intersecting lines across it ... well, for a picture that was supposed to be a tribute to one of the most intricately constructed compositions ever? Sorry, Pig. Sorry, Wood. I let you both down. The window is ... just off to the left; the pitchfork is ... just off to the right. The Frog’s collar button and the Pig’s cameo do not exactly mirror each other across the centre point ...

“How could this one have ended up missing the mark so widely? It drives me nuts to this day ... All I can plead is that I did my best (you know — that road to hell ...), and then the time ran out. Which is, one hopes, at least what one can say about one’s life.”

•For Mr Frith’s full essay, see the Royal Academy of Art website here https://www.royalacademy.org.uk/article/american-gothique-muppet-masterpiece