The human body is 108 fingers tall. The width of your outstretched arms is equal to your height, and makes a perfect square with your groin as the center. Your limbs axis of rotation forms a circle, with your belly button as the center. Vitruvius believed that these geometric approximations showed that man was created from a divine source (circle) and was tied to it from birth (belly button). But that man also exists in a material world (square) and is destined to stay there for the future (groin).