Leonardo's “Vitruvian Man” is perhaps the most reproduced drawing ever made. Leonardo probably inked this drawing during the 1490s when he was starting to study “divine proportions” with Fra Pacioli, a noted mathematics professor and philosopher. Much has been written about the symbolism of this drawing. There is little question that the basic concept derives from statements on proportions by the Roman architect Vitruvius, whom Leonardo refers to underneath the drawing. Much debated is the question of what else was in Leonardo’s mind. Was he trying to “square the circle” in an Alchemical manner? Perhaps. Did he actually divide all the major parts of the human body into segments that correspond to what Pacioli, Leonardo’s teacher, called the “Divine Proportion,” a proportion that also is known as the Golden Ratio? Perhaps. It also may well be that Leonardo’s intention was to represent the ideal harmony that the circle & square have represented for centuries in the sacred art of the great spiritual traditions. In Taoism, Hinduism, Buddhism, Christianity, and Islam the square symbolizes the material world and the circle symbolizes the spiritual dimension that permeates all of matter. Said another way, the Microcosm is a reflection of the Macrocosm. (FLG)

Article on the use of "golden proportions": http://bit.ly/2Zpr3tJ