Today, Earth, Air, Fire, and Water. The University
of Houston's College of Engineering presents this
series about the machines that make our
civilization run, and the people whose ingenuity
created them.
Western chemistry grew up
around alchemical ideas of Earth, Air, Fire, and
Water. They're called the Aristotelian
elements, but they originated with a much
earlier thinker -- the Sicilian aristocrat,
Empedocles of Acragas.
Not many of Empedocles' writings have survived, and
a large mythology now hovers over his person. We
have fragments of two book-length poems One was an
exploration of nature itself. The other dealt with
personal salvation.
He probably wrote plays, and treatises on medicine,
as well. Aristotle credited Empedocles with
inventing rhetoric, and with the idea that light
moves at a finite speed. But Empedocles is best
known for claiming that all matter is formed when
the opposing forces of Love and Hate act upon the
four elements -- Earth, Air, Fire, and Water.
He also gave us an early theory of natural
selection. His biographer Alexander Mourelatos
tells how he explained the origins of animals by
"imagining random combinations of stray limbs and
organs." At first, those combinations produced only
monsters, but viable arrangements eventually
emerged; and they survived.
Although Darwin quoted Aristotle's discussion of
Empedocles' evolutionary ideas, Empedocles stopped
where Darwin began. His creatures, once randomly
created, were either fit to survive or not.
Darwinian natural selection continued from that
point -- im-proving the ability of living things to
function.
So many remarkable ideas well up from Empedocles.
He talked about matter and mechanical force, about
attractive and repulsive forces, about mass and
energy conservation. Freud wondered aloud if his
own views of Love and Hate were subconsciously
influenced by his early readings about Empedocles.
No force as large as Empedocles could reach us, all
the way from prehistory, without picking up legends
along the way. One such legend tells about how he
was so convinced of his own immortality that he
leapt into the crater of Etna. In another, he
simply ascended into the sky. Mourelatos tells how,
in the nineteenth century, Sicilian supporters of
Garibaldi took Empedocles as the prototype of their
hero -- the aristocrat in a populist cause.
When Aristotle got his hands on Earth, Air, Fire,
and Water, the world shifted. Now the external
forces that acted upon the essences would no longer
be Love and Hate. Now their physical coun-terparts
transmuted matter -- heat and cold, or dampness and
dryness. The evolution of chemistry was beginning.
So Empedocles still rises like smoke from Etna. He
reminds us that the primal scientific issue may not
be a simple matter of judging what is true and
false. Perhaps science is the business of
recognizing ideas that have the capacity for
evolving into ever more useful explanations of the
vast cosmos around us.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
A. P. D. Mourelatos, Empedocles of Acragas.
Dictionary of Scientific Biography (C.C.
Gilespie, ed.). New York: Charles Scribner's Sons,
1970-1980.
Click here for more on Empedocles.
(photos by John Lienhard)
The Engines of Our Ingenuity is
Copyright © 1988-2003 by John H.
Lienhard.
