Long before the explosion of evolutionary ideas during the mid-19th century, scholars of various stripes arranged all of nature according to an intricately graded scale called the Great Chain of Being. Rooted in the ruminations of Plato and Aristotle, but most famously adopted by Medieval theologians and Renaissance thinkers, this concept ranked the natural world into a static hierarchy which elucidated the character of the Almighty. The chain was not a ramshackle assemblage of minerals, plants, and animals, but instead a carefully ordered sequence of increasing complexity and closeness to God in which our species occupied a crucial hinge point—animal in body but infused with a divinely-prescribed soul.