Today, guest scientist Andrew Boyd persuades us.
The University of Houston presents this series
about the machines that make our civilization run,
and the people whose ingenuity created them.
Every day we're faced with
people who want to persuade us: salesmen want our
money, politicians want our vote, and our children
want to stay up past their appointed bedtime. We
put up with it because, well, it's just part of
But, to the ancient Greeks, persuasion was more
than a nuisance. It was a highly respected skill,
something to be studied and perfected. The term
used by the Greeks was rhetoric, which
today not only refers to persuasive communication,
but communication that is overly complex or
pretentious. To the Greeks, however, rhetoric meant
persuasion, without those negative overtones.
Greek education began with the study of grammar,
logic, and rhetoric. These three subjects were
considered so important they even had their own
name - the trivium, which means "the
three roads." While grammar and logic seem
reasonable choices for the foundation of education,
how did rhetoric wind up in the mix?
Rhetoric was popularized in the fifth century B.C.
by the sophists. The sophists began as a respected
group of educators paid to teach rhetoric as a
practical skill, useful in a democratic society.
But as sophist rhetoric evolved, it became more and
more focused on winning an argument to the
exclusion of all else. Today, we use the word
sophistry to describe an argument that
sounds good but is mis-leading or downright false.
Sophist rhetoric was attacked by Plato, who
believed in arguments based on logic. To Plato,
logical arguments led to truth, a far nobler goal
than simply winning an argument.
But it was Plato's greatest student, Aristotle, who
would fashion a respectable vision of rhetoric that
would dominate western thinking for the next two
thousand years. Like Plato, Aristotle firmly
believed that logic was absolutely essential when
constructing an argument. But he went further,
emphasizing things like appealing to the emotion of
listeners, good presentation skills, timing, and
how the mood of an audience influences what they
hear. Where Aristotle differentiated himself from
the sophists was in his focus on the process of
creating a persuasive argument rather than on
winning at all costs.
Aristotle brilliantly clarifies his position in the
very first sentence of his book, The Art of
Rhetoric, where he refers to rhetoric as the
counterpart to Plato's logic. Logic is required to
find truth, but rhetoric is necessary to
Here we see why rhetoric is viewed as so essential
to Greek education. Persuasive communication isn't
an unpleasant afterthought, it's a vital part of
bringing ingenious ideas to life. For those of us
accustomed to letting the facts to speak for
themselves -- especially scientists and engineers
-- perhaps there is a lesson to be learned from the
Greek emphasis on rhetoric: So much of what we hear
today should not be called rhetoric. Communication
and truth must be made to go hand in hand. It is in
this sense that communication is as important as
the message we carry.
I'm Andy Boyd, at the University of Houston, where
we're interested in the way inventive minds work.
An updated version of this episode can be found at 3051.
Dr. Andrew Boyd is Chief Scientist and Senior Vice
President at PROS, a pricing and revenue optimization
software firm. Dr. Boyd received his A.B. with Honors
at Oberlin College with majors in Mathematics and
Economics in 1981, and his Ph.D. in Operations
Research from MIT in 1987. Prior to joining PROS, he
enjoyed a successful ten year career as a university
Information on classical rhetoric is widely
available on the web. See, e.g.:
Dialectic is sometimes translated as logic in the
classical sense; see, e.g.:
We use the word logic to avoid discussing dialectic
in the limited time available.
Detail of Plato teaching Aristotle from a much
larger painting by Raphael: The School of
The Engines of Our Ingenuity is
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