FIFTH ELEMENT

According to Galen, these elements were used by Hippocrates in describing the human body with an association with the four humours: phlegm (water), yellow bile (fire), black bile (earth), and blood (air).

Some cosmologies include a fifth element, the "quintessence."

The Pythagoreans added idea as the fifth element, and also used the initial letters of these five elements to name the outer angles of their pentagram.

Aristotle added aether as the quintessence, rationalizing that whereas fire, water, earth, and air were earthly and corruptable, the stars were eternal ("aether" is based on Greek for eternity) and were thus not made out of any of the four elements but rather a heavenly substance. The word aether was revived by early 20th century physicists as a term for the invisible medium which permeated the universe. The non-existance of aether was to lead to the downfall of Newtonian physics and pave the way for Einstein's theories of relativity.

Chinese Classical Elements

In Chinese Taoism there is a similar system, which includes metal and wood but excludes air. Different things in nature are associated with the five types. For example, the five major planets were named after the elements: Venus is metal, Jupiter is wood, Mercury is water, Mars is fire and Saturn is earth. Also the Moon represents Yin, the Sun represents Yang. Yin and Yang and the five elements are recurring themes in the I Ching, which is strongly related to Chinese cosmology and astrology. See Chinese five elements.

Some South Asian traditions also include the air, earth, fire, water distinctions.

Warning: Wikipedia contains spoilers

Every five millennia, when Evil arrives, Earth is guarded by the Mondoshawans, who pose as Lords to their priests. The Mondoshawan guardians placed five powerful elements in a temple in Egypt eons ago. The first four -- water, fire, earth, and air -- are in the form of small elongated cubic stones, and the Fifth Element encased in a sarcophagus in a shape of a person mouth widely open facing upward.

In 1914, the Mondoshawan guardians took the elements away and returned 300 years later with the Fifth Element, when the Evil also returns as a black sphere that communicates with its human puppets telepathically. The first four elements were bestowed by the Mondoshawans to a sky-blue alien opera singer, Plavalaguna, for protection. (It is interesting that "plava laguna" means "blue lagoon" in Serbian language; this is a reference to Mila Jovovich's first film, Return to the Blue Lagoon.)

Zorg (Oldman), a puppet, orders the destruction of the travelling Mondoshawan spaceship. The Earthlings are, however, able to retrieve from the crash site a decapitated hand within a glove, which were regenerated to reveal Leeloo, an amazingly intelligent and strong Fifth Element. Leeloo, however, immediately escapes the laboratory cage and dove into Korban's taxicab.