aether is the material that fills the region of the universe that stretches beyond the moon. aether is the explanation for gravity and the traveling of light. aether is one of the first entities to come into existence, the first element. aether permeates the entirety of universe, and exists even in the vacuum. aether is the pure essence that the gods breathe, the air of divinity. aether is the son of erebus, of darkness, and nyx, of the night. aether is the brother of hermera, of day. plato says that it is the purest of oxygens, aristotle says it is an element fifth. he says it moves in circles; and is neither wet nor dry; neither hot nor cold. he says that aether contains all celestial bodies, in crystallized spheres. robert fludd says that aether is subtler than light.