Around 1490 in Milan, Leonardo da Vinci drew the Vitruvian Man, a study of human proportions inspired by the Roman architect Vitruvius. Leonardo’s sketch shows a nude male figure in two overlapping poses—arms and legs splayed—to fit both a circle and a square, symbolizing the harmony between human anatomy and geometric perfection. Vitruvius had written that a well–proportioned building should mirror the ideal human body, and Leonardo took those canonical ratios—such as a palm being the width of four fingers or the span of a man’s arms equaling his height—and refined them with his own measurements and observational drawings. More than an anatomical chart, the drawing embodies High Renaissance ideals: art and science fused. Leonardo annotated the figure with notes detailing each unit of measure, while the interlocking shapes hint at a cosmic order in which man, the microcosm, reflects the universe, the macrocosm. After being passed to his pupil Francesco Melzi, the sketch eventually entered Venetian collections, where Giuseppe Bossi in the early 19th century first published scholarship on it. In 1822 it was acquired by Venice’s Gallerie dell’Accademia, remaining there since. Because of its sensitivity to light, the Vitruvian Man is rarely shown publicly, though it has traveled for landmark exhibitions—most recently to the Louvre in 2019 for the 500th anniversary of Leonardo’s death—continuing to stand as an enduring icon of Western art, science, and the humanist vision.