ling.
That he was a keen student of nature is witnessed by many recorded
observations in anatomy and physiology; he reasoned that sensations
travel by definite paths to the brain. But our attention must be
confined to his introduction of the theory of the four elements--fire,
air, earth and water--of which, in varying quantities, all bodies were
made up. Health depended upon the due equilibrium of these primitive
substances; disease was their disturbance. Corresponding to those were
the four essential qualities of heat and cold, moisture and dryness, and
upon this four-fold division was engrafted by the later physicians the
doctrine of the humors which, from the days of Hippocrates almost to our
own, dominated medicine. All sorts of magical powers were attributed to
Empedocles. The story of Pantheia whom he called back to life after a
thirty days' trance has long clung in the imagination. You remember
how Matthew Arnold describes him in the well-known poem, "Empedocles on
Etna"--

But his power
Swells with the swelling evil of this time,
And holds men mute to see where it will rise.
He could stay swift diseases in old days,
Chain madmen by the music of his lyre,
Cleanse to sweet airs the breath of poisonous streams,
And in the mountain-chinks inter the winds.
This he could do of old--(5)

a quotation which will give you an idea of some of the powers attributed
to this wonder-working physician.

(5) Poetical Works of Matthew Arnold, Macmillan & Co., 1898,
p. 440.

But of no one of the men of this remarkable circle have we such definite
information as of the Crotonian physician Democedes, whose story
is given at length by Herodotus; and his story has also the great
importance of showing that, even at this early period, a well-devised
scheme of public medical service existed in the Greek cities. It dates
from the second half of the sixth century B.C.--fully two generations
before Hippocrates. A Crotonian, Democedes by name, was found among the
slaves of Oroetes. Of his fame as a physician someone had heard and he
was called in to treat the dislocated ankle of King Darius. The wily
Greek, longing for his home, feared that if he confessed to a knowledge
of medicine there would be no chance of escape, but under threat of
torture he undertook a treatment which proved successful. Then Herodotus
tells his story--how, ill treated at home in Crotona, Democedes went to
AEgin