For centuries, people in the ancient world believed that water could be transmuted into air through fire. We can probably safely attribute this to the fundamental properties attributed to the ethereal element by the classical philosophers. Air is hot and wet, linking it to both fire and water on the wheel of elemental rotation where the underlying theory of shared characteristics explains why one element can transmute into another. Anaximenes of Miletus (mid-6th-century bce) was the first pre-Socratic philosopher to attach a special significance to air, naming it as the element of which the primary chaos and Empyrean of God was composed. This conviction was inherited by esoteric and practical alchemy in late antiquity, and immortalised in an eighth-century Arabic text by Jabir ibn Hayyan (which would become known and popularised as the Emerald Tablet) which says of the Philosopher’s Stone, “The wind carried it in its womb.” Hence the element was so important in esoteric thought that it was even imagined to be the womb which brought forth the elusive and transcendent Stone itself.
Alchemy’s veneration of the element is completely logical, given that the Pre-Socratic philosophers including the likes of Anaximenes of Miletus and Diogenes Apolloniates (late 5th century bce) whom influenced ideas pertaining to the first differentiation of matter were initially convinced that ethereal air was the very fabric holding the tapestry of woven threads of created nature together. Air is an active, masculine element and its two fundamental properties are hot and moist, or wet. Just like its material counterpart, the element is inextricably associated with volatility, expansion and becoming, but also with the condition of death and sleep, the cardinal direction of north, the colour black and the quality of falsehood. If the four elements were ordered according to the compass of all possible movements, it would come second, after fire. Its primary tendency is to rise and extend. In all esoteric currents, including chemico-operative and spiritual-philosophical alchemy, air is symbolised by a triangle bisected by a horizontal line.