The Great Chain of Being

The concept of the "Great Chain of Being" begins with a marriage of Plato's Idea of the Good who is bound by its own principle of plenitude to generate every possible Idea and temporal being, and Aristotle's Scala Natura (Ladder of Nature). The Neoplatonists modified Plato's conception of concept of a somewhat abstract plenitude of being by "metaphysicalising" it, turning it into a series of discrete (but inter-raying) hypostases, in which the higher hypostases gives rise to the next one down, and so on. So Plotinus' cosmology was less one of a Great Chain of Being and more one of a series of emanations. However, with the fall of classic learning this last formulation of pagan thought was lost, and the middle ages reverted to the more classic Platonic and Aristotlean approach (via Augustine and Aquinus).

According to the historian of ideas Arthur Lovejoy, there thus resulted a

"conception of the plan and structure of the world which, through the Middle Ages and down to the late eighteenth century...most educated men were to accept without question - the conception of the universe as a "Great Chain of Being", composed of an immense, or...infinite, number of links ranging in hierarchical order from the meagerest kind of existents...through "every possible" grade up to the ens perfectissumum."

The metaphor of a Great Chain of Being plays a big part is in 17th and 18th century thought (which much of Lovejoy's The Great Chain of Being deals with), and where among other things it contributed to German Idealistic and nature philosophy, and ultimately the evolutionary thinking of Lamarck. Lamarck's evolutionary theory was nothing but a "Temporalisation of the Great Chain of Being" [see Frederick Gregory,  J.-B. Lamarck and the philosophy of nature in France, before being discredited by the Darwinian revolution and the scientific emphasis on empirical facts. Associated with the Great Chain is the concept of the Four Kingdoms. A revival of this evolutionary Great Chain of Being is found in Theosophy and more recently Edward Haskell, Oliver Reiser, Erich Jantsch, Ken Wilber, and others.