In the esoteric language, the four elements are not to be confused with the four corporeal manifestations of the same name. They are merely the initial or primary differentiations of the primal virginal substance of all creation, the prima materia. All of them exhibit two of four secondary properties–hot, cold, dry and moist. This theory came down to us through the Aristotelian doctrine of matter, though it most probably took shape under the philosophical musings of the Ionic pre-Socratics. The ethereal element of water is cold and moist, and its material manifestation as a composition of two atoms of hydrogen and one of water (H20) is an immediate and exoteric expression of the former’s quintessential aspects–its volatility, passivity, amorphousness, colourlessness and receptivity. Water is characterised by the condition of heaviness, but also of expansion. On a scale which orders the four ethereal elements on the basis of their pureness and level of refinement, water would come third, after both air and fire. Unlike the latter two which tend to rise, water is rather dense and possesses a downward tendency. Nevertheless it’s not as heavy, invariable and sluggish as the element of earth. In alchemical manuscripts and other esoteric documents, it is symbolised by an overturned triangle.