Dentist cracks mystery of world famous Da Vinci drawing after 500 years

It is one of the most famous – and mystifying – drawings in human history.

Leonardo da Vinci’s Vitruvian Man was the attempt by the famous Italian artist to construct the perfectly proportioned male body 500 years ago.

But mathematicians have spent years trying to crack the question of how he was able to place the human figure inside a circle and a square.

Now, a London-based dentist has uncovered a hidden detail in Da Vinci’s masterpiece, which he says reveals the answer.

Dr Rory Mac Sweeney points to an equilateral triangle ‘hidden in plain sight’ in the Italian’s notes, which lays the foundation of the drawing’s perfect proportionality.

The triangle, found between the man’s legs, ‘isn’t just a random shape’, Dr Sweeney says, but corresponds to a little-known concept called Bonwill’s triangle.

Bonwill’s triangle is a concept in dental anatomy which is used to understand how human jaws work.

The imaginary triangle connects the left and right jaw joints with the spot between your two bottom front teeth – each side is four inches long.

The fact that da Vinci was using this shape in a drawing sketched in 1490 drawing reveals his genius understanding of the human body centuries before modern science came along, Dr Sweeney argues.

Here is where it gets a little bit mathsy. When you use one of these triangles in the Vitruvian Man, you can calculate a ratio between the size of the square and the circle in the famous drawing.

That ratio is 1.64, which is almost identical to a very important number – 1.6333.

That number is called the ‘special blueprint number’, which you can find everywhere in the most efficient structures in nature.

That number pops up everywhere – even stacking oranges – because it governs the tightest way to pack spheres, among other things.

Dr Sweeney, who graduated from the School of Dental Science at Trinity College in Dublin, said: ‘We’ve all been looking for a complicated answer, but the key was in Leonardo’s own words.

‘He was pointing to this triangle all along. What’s truly amazing is that this one drawing encapsulates a universal rule of design.

‘It shows that the same “blueprint” nature uses for efficient design is at work in the ideal human body.

‘Leonardo knew, or sensed, that our bodies are built with the same mathematical elegance as the universe around us.’

The dentist argues his discovery shows the Vitruvian Man is not a beautiful drawing, but a work of ‘scientific genius that was centuries ahead of its time’.

Sweeney believes he has solved the riddle first set by Roman architect Marcus Vitruvius Pollio hundreds of years ago.

He said the human body has harmonious proportions, and theorised it could fit perfectly inside a circle and a square, but never outlined how that could be done.

Da Vinci then came long and drew exactly that, but never explained how.

Sweeney believes his theory puts to bed centuries of speculation as to what measurements the Italian polymath used.

The study, published in the Journal of Mathematics and the Arts, reads: ‘For over 500 years, Leonardo da Vinci’s geometric system for establishing the precise relationship between the circle and square in his Vitruvian Man drawing has remained a mystery.

‘This paper demonstrates that Leonardo’s explicit textual reference to “an equilateral triangle” between the figure’s legs provides his construction method and reveals the anatomical foundation for his proportional choices.

‘The analysis shows that Leonardo’s equilateral triangle corresponds to Bonwill’s triangle in dental anatomy – the foundational geometric relationship governing optimal human jaw function.’

Not long after the Vitruvian Man came into being, Da Vinci painted one of the most important religious paintings ever – The Last Supper.

The depiction of Jesus and his disciples was then followed by the most famous artwork of them all, the Mona Lisa, in the early 1500s.

The painting attracts millions of visitors annually at the Louvre Museum in Paris alone.

Other than his artwork, Da Vinci is known for his vast array of talents.

He was also a sculptor, architect, musician, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist, and writer.

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