The Four Elements in Greek Cosmology
Greek philosophy supposed the Universe to comprise four elements: Fire, Water, Earth, and Air. Air was originally supposed to be a component of the Æther [ether, not to be confused with the gas], the element that filled the Universe in the absence of the other three. Empedocles referred to these as "roots" (rhizomata, ῥιζώματα), and proved that Air was a separate element by showing that a bowl filled with air inverted in water did not immediately fill with water, but retained a pocket of air. Notice that this shows by experiment that Air is something, rather than nothing. Aristotle was the first to call these roots "elements" (stoicheion, στοιχεῖον), the smallest unit of time on a sundial, or an indivisible unit. The same root appears in Stoichiometry, the branch of chemistry that deals with ratios between reactants and products. Note that the diagram includes multiple paired associations and opposites, in keeping with Aristotelian notions of dichotomy. Cold / Hot, and Wet / Dry are paired across the diagram. Water and Fire are fundamentally contrasted: fire rises, water falls (note directionality of their paired alchemical symbols). Water is by nature wet and cold, features it shares with Air and Earth, respectively. Fire is hot and dry, also shared in the same way. Air is wet or hot, according to the balance of moisture and heat. Transformations among Ice, Water, & Steam are not specifically accommodated in this scheme. The Four Elements can also be arranged in ascending order, from lower to higher. Earth rises out of Water, Air is above the Earth, and the Sun (Fire) is over all. (Al)Chemical reactions occur as the reactants try to return to their proper place in the series.
Other cultures recognize analogous arrangements. The Oriental I Ching (Book of Changes) comprises 64 hexagrams, each comprising two trigrams placed one on the other. Each trigram comprises three lines, broken Yin (--- ---) or unbroken Yang (-------). As there are 23 = 8 trigrams, there are 8
2 = 64 hexagrams. Divination is practiced by focused attention to a question, then composition of six Yin / Yang lines for the two trigrams. The oracle is consulted for the hexagram: as the same lines may be formed in different ways, moving or static, which adds further depth to the divination. The trigrams represent combinations of the same concepts of Fire, Water, Earth, & Air. For example, if trigram 7 for Fire occurs above trigram 8 for Water, this produces hexagram 38, "Fire in the Lake", the symbol of Revolution, used as the title of Frances Fitzgerald's Pulitzer-Prize winning history of Americans in Vietnam.Many commentators have noted the analogy between 64 in the I Ching and the Genetic Code, the latter as obtained as 43 = 64 triplets. It may be noted that the third (uppermost) line in any trigram has the least influence on meaning, just as the third letter of the Genetic Code may have little (two-fold degenerate) or no (four-fold degenerate) on the amino acid encoded.
All text material © 2022 by Steven M. Carr
