Aether (classical element)

According to ancient and medieval science aether (Greek aithēr), also spelled æther or ether, is the material that fills the region of the universe above the terrestrial sphere.
==Mythological origins==
The word (aithēr) in Homeric Greek means "pure, fresh air" or "clear sky", imagined in Greek mythology to be the pure essence where the gods lived and which they breathed, analogous to the air breathed by mortals (also personified as a deity, Aether, the son of Erebus and Nyx). It is related to "to incinerate",Pokorny, Julius (1959). Indogermanisches etymologisches Wörterbuch, s.v. ai-dh-. also intransitive "to burn, to shine" (related is the name Aithiopes (Ethiopians)), meaning "people with a burnt (black) visage". See also Empyrean.
==Fifth element==
In Plato's Timaeus (St-55c) Plato described aether as "that which God used in the delineation of the universe."
Aristotle (Plato's student at the Akademia) included aether in the system of the classical elements of Ionian philosophy as the "fifth element" (the quintessence), on the principle that the four terrestrial elements were subject to change and moved naturally in straight lines while no change had been observed in the celestial regions and the heavenly bodies moved in circles. In Aristotle's system aether had no qualities (was neither hot, cold, wet, or dry), was incapable of change (with the exception of change of place), and by its nature moved in circles, and had no contrary, or unnatural, motion.G. E. R. Lloyd ), Aristotle: The Growth and Structure of his Thought, Cambridge: Cambridge Univ. Pr., 1968, pp. 133-139, ISBN 0-521-09456-9. Medieval scholastic philosophers granted aether changes of density, in which the bodies of the planets were considered to be more dense than the medium which filled the rest of the universe.E. Grant, Planets, Stars, & Orbs: The Medieval Cosmos, 1200-1687, Cambridge: Cambridge Univ. Pr., 1994, pp. 422-428, ISBN 0-521-56509-X. Robert Fludd stated that the aether was of the character that it was "subtler than light". Fludd cites the 3rd century view of Plotinus, concerning the aether as penetrative and non-material.Robert Fludd, "Mosaical Philosophy". London, Humphrey Moseley, 1659. Pg 221. See also Arche.
==The quintessence, as used in alchemy==
The quintessence, or fifth element, was a term used by medieval alchemists for a substance similar or identical to that thought to make up the heavenly bodies. It was proposed that a little of the quintessence was present in things on earth, meaning that things on earth could be affected by what happened in the heavens.The Alchemists, by F. Sherwood Taylor page 95
This theory was developed in the text “The testament of Lullius”, attributed to Raymond Lull and written in the early 14th century. Alchemy then dealt with the isolation and use of this fifth element.The Alchemists, by F. Sherwood Taylor page 95
The idea spread with rapidity through Europe and was popular with later alchemists, especially of the medical sort. This can be seen in “The book of Quintessence”, a 15th-century English translation of a continental text. In it, the quintessence is used as a medicine for man’s illnesses, and instructions are given for making it from seven times distilled alcohol.The book of Quintessence, Early English Text society original series number 16, edited by F. J. Furnivall
The term has over the years become synonymous with elixirs, medicine or the philosopher’s stone itself.The dictionary of alchemy, by Mark Haeffner
==Legacy==
While special relativity showed that Maxwell's equations do not require the aether, there were some early modern aether theories. However, the early modern aether has little in common with the aether of classical elements from which the name was borrowed and the aether theories are scientifically obsolete.
==See also==
* Akasha
* Plane (esotericism)
==References==
; General
* FAQ - The Ancient Elements of Nature Ancient proto-scientific conceptualisations of the domain of nature into its constituent elements: Earth, Water, Air, Fire and Aether.
; Specific
Category:Classical elements
Category:Obsolete scientific theories
Category:Aether theories