ctures in the world—fire, air, water, earth. PO] Empedocles called these four elements "roots", which he also identified with the mythical names of Zeus, Hera, Nestis, and Aidoneus [31] (e.g., "Now hear the fourfold roots of everything: enlivening Hera, Hades, shining Zeus. And Nestis, moistening mortal springs w