Leonardo’s drawing Vitruvian Man illustrates the theories on proportion postulated by the Roman architect Vitruvius in the first century B.C. It demonstrates ‘the golden ratio’, or perfect proportion in relation to the human body.
The Golden Ratio is a harmonic relationship between elements of a form that occurs throughout nature. For Renaissance thinkers, such ratios were mathematically and aesthetically pleasing and fundamental to the structure of the universe. Ideally, a perfect human body would reflect these perfect proportions.
The drawing depicts a man in two different positions, one set in a square and the other in a circle. The man’s navel marks the centre of the circle whilst his genitals mark the central point of the square. The height of the figure corresponds to eight times the height of the head. The arm-span is also equal to the man’s height, and the length of his foot is one-seventh of his height. Many other ratios are noted by Leonardo in his commentary on the drawing.
Leonardo’s drawing combines a careful reading of Vitruvius’ text with his own observations of the human form. He was the first naturalist who turned to mathematics for a key to the understanding of anatomy.