The Six Elements: Visions of a Complex Universe

There are rosebushes in front of my house, and sometimes I step outside to stand among them, enjoying the look and scent of their blooms. I was raised in the city, and it still surprises me to see growing things spring from the earth. That may be why, as I pick up a handful of earth, I think how remarkable it is that its matter-of-fact grittiness leads to the intricate beauty of roses. It is natural for one then to think of Earth on a larger scale as one of the Four Elements of antiquity.

Earth, Air, Fire and Water: All relate to growing things, and furthermore to life on our planet, to the structure of the planet itself, ultimately to all nature. The meaning of Earth, for instance, extends far beyond that of the rough, pragmatic material I can hold in my hand; it is the brute bulk of our world, expressed in massive geological formations, the substance of other worlds, the dense interiors of dead stars. It is precious minerals, useful ores from deep mines and the exquisitely refined gemstones and solid materials we make from those raw substances.

With that last realization, I see that the archaic idea of Earth is still significant. Physicists study solids in laboratories, where it is easy to forget that they come from nature. It is at first startling, and then illuminating, to re-connect them to their origin, the element Earth. Water, Air and Fire also have meaning in modern science. Water and Air correspond to liquids and gases, the other two great categories of matter; Fire can be interpreted as light, an energy that has always filled the universe, and as flame and heat.

Early philosophers considered two more categories: Void, the emptiness that contains matter, and Quintessence, a substance that forms the distant cosmos. These too have modern counterparts. Void is the vacuum beyond our atmosphere; as what physicists call the vacuum state, it is where the universe began. Quintessence corresponds to "dark matter"—the invisible material that is unlike anything on this planet and that makes up at least nine-tenths of the cosmos—and to "dark energy," the equally mysterious antigravity that is accelerating the expansion of the universe.

These ancient groupings are counterweights to the reductive style of modern science, which emphasizes nature's smallest units. This approach is highly successful, giving deep insights, for example, into the quantum nature of reality and the significance of DNA. However, it does not span the full picture that began 13 billion years ago with the Big Bang. The Six Elements—the Four plus Quintessence and Void—are universal categories that engender coherent visions of the physical universe, visions with artistic as well as scientific meaning and the power to bridge those areas.

Two Greek thinkers in the 6th century B.C.E. first conceived the natural Elements. To Anaximenes, everything was made of Air. Rarefied, it became Fire, which formed the Sun; condensed, it became Water and Earth. Thales took Water as primary; "All things are water," he wrote. A century later, the philosopher Heraclitus thought Fire was the basic substance.

A universe made from a single substance is elegantly simple, but a better model for the world's diversity came from the Greek philosopher Empedocles, born in Sicily around 495 b.c.e. A figure of mystical power, he was said to be able to raise the dead and later to have thrown himself into Mount Etna's crater to join the gods. His great accomplishment is the idea that Earth, Air, Fire and Water form what lies around us, brought together or kept apart by Love and Strife. This brilliant scheme is broad enough to describe great swatches of the cosmos, yet sufficiently articulated to explain much. Bone, for instance, is Earth and Water blended together by the application of Fire, all in the proportion 1:1:2. Human vision occurs as Water modifies Fire; that is, the vitreous humor in the eye affects the visual ray, which in Empedocles' time was thought to come from the eye.

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