beside fire, water, earth, and air the element that is necessary to
explain the diversity and multiplicity of life, the finest or
best of any
substance. The quintessence is an element that permeates all nature
and is the constituent matter of the celestial bodies.
The scholastics of the Middle Ages believed it to be the ether, the substance above the sphere of fire, and of which the human soul was made.
In medieval alchemy the quintessence was the best part of a chemical substance that could be extracted with chemical methods. The alchemists therefore also used it for alcohol, the best or finest part of wine.
For the more esoteric alchemists the quintessence and lapis philosophorum, the Stone of the Wise, were closely associated, and sometimes synonymous entities.
Some say that the idea of a fifth element came from the Pythagoreans.
The Chinese also counted five elements. For them, metal was the fifth element.
A synonym is .