The great chain of being is a hierarchical structure of all matter and life, thought by medieval Christianity to have been decreed by God. The chain begins with God and descends through angels, humans, animals and plants to minerals.[1][2][3]
^"This idea of a great chain of being can be traced to Plato's division of the world into the Forms, which are full beings, and sensible things, which are imitations of the Forms and are both being and not being. Aristotle's teleology recognized a perfect being, and he also arranges all animals by a single natural scale according to the degree of perfection of their souls. The idea of the great chain of being was fully developed in Neoplatonism and in the Middle Ages.", Blackwell Dictionary of Western Philosophy, p. 289 (2004)
^Edward P. Mahoney, "Lovejoy and the Hierarchy of Being", Journal of the History of Ideas Vol. 48, No 2, pp. 211-230.