Overview

• The Journal of Mathematics and the Arts published Dr Rory Mac Sweeney’s research on July 2, revealing the overlooked triangle.
• Leonardo’s notes instruct that opening the legs to form an equilateral triangle anchored the figure’s navel as the center of his circle.
• The triangle mirrors William Bonwill’s 1864 dental blueprint for optimal jaw mechanics, linking Renaissance art to anatomical function.
• This construction yields a square side to circle radius ratio of about 1.64, outperforming Golden Ratio–based theories.
• The discovery suggests da Vinci anticipated modern anatomical and geometric principles centuries before their formal development.