The Body Electric - Micro-ondes

62 The Body Electric
the plant's own current, restitution was delayed by two or three weeks.
To American biology, however, this was all nonsense. To understand
why, we must backtrack for a while.
Luigi Galvani, an anatomy professor in the medical school at the Uni-
versity of Bologna who'd been studying electricity for twenty years, first
discovered the current of injury in 1794, but unfortunately he didn't
know it.
At that time, biology's main concern was the debate between vitalism
and mechanism. Vitalism, though not always called by that name, had
been the predominant concept of life since prehistoric times throughout
the world, and it formed the basis for almost all religions. It was closely
related to Socrates' and Plato's idea of supernatural "forms" or "ideals"
from which all tangible objects and creatures derived their individual
characteristics. Hippocrates adapted this idea by postulating an anima as
the essence of life. The Platonic concept evolved into the medieval phi-
losophy of realism, whose basic tenet was that abstract universal princi-
ples were more real than sensory phenomena. Mechanism grew out of
Aristotle's less speculative rationalism, which held that universal princi-
ples were not real, being merely the names given to humanity's attempts
at making sense of the reality apprehended through the senses. Mecha-
nism had become the foundation of science through the writings of Des-
cartes in the previous century, although even he believed in an
"animating force" to give the machine life at the outset. By Galvani's
time, mechanism's influence was steadily growing.
Galvani was a dedicated physician, and medicine, tracing its lineage
back to tribal shamans, has always been a blend of intuition and em-
pirical observation based on a vitalistic concept of the sanctity of life.
The vitalists had long tried—unsuccessfully—to link the strange, incor-
poreal phenomenon of electricity with the elan vital. This was Galvani's
main preoccupation.
One day he noticed that some frogs' legs he'd hung in a row on his
balustrade, pending his dinner, twitched whenever the breeze blew them
against the ironwork. At about the same time his wife Lucia noticed in
his laboratory that the muscles of a frog's leg contracted when an as-
sistant happened to be touching the main nerve with a steel scalpel at
the same instant that a spark leaped from one of the electrical machines
being operated across the room. (The only type of electricity then known
was the static type, in the form of sparks from various friction devices.)
Today we know that an expanding and collapsing electric field generated
by the spark induced a momentary current in the scalpel, which stimu-
lated the muscle, but Galvani believed that the metal railing and scalpel
had drawn forth electricity hidden in the nerves.