Earth, Water, Air and Fire are four recurring elements of classical thought, cross-culturally. Quintessence (borrowing the etymological stem ÔquintÕ for ÔfifthÕ) is a recurrent fifth element. In ancient India and Greece, this fifth element is called ÔAetherÕ, which is also the etymological root of the ÔethernetÕ, the computer networking architecture often distributing the internet. In ancient and medieval philosophy as a ubiquitous fifth element, quintessence is present in nature as well as celestial bodies in its ÔpurestÕ and most Ôconcentrated formÕ.