The belief in a hierarchical structure to the universe, from God down to angels, fallen angels (or demons), astronomical features, royalty, common folk, animals, plants, and down to precious and then common minerals. The concept began with Plato and Aristotle, but achieved a high level with the Neoplatonists and Kabalists. Since this structure was believed to be decreed by God, it gave royalty—including kings, queens, princes, and all nobles—superiority over common people, a belief that existed until the Enlightenment that began in the late 17th century and culminated in the American and French Revolutions.