Today, the quotidian denominator. 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.
I asked a reference librarian
if he had one of those little three-by-five pieces
of paper so I could write down a catalog number.
(Those slips are usually found on the counter in
small wooden boxes, along with short pencils.) He
took mock offense: "Please, John, those
'little pieces of paper' have a name;
they're called P-slips."
That arcane fact, unknown even to many librarians,
set me to thinking about specialized words. When
someone in an on-line library discussion asked,
"What do you call a ribbon, attached to the spine
of a book, for marking pages?" the debate lasted
two days. They finally settled on the improbable
word, signet. Then someone said, "Why don't
you just call it a ribbon page-marker?"
We engineers are every bit as guilty of this
arcanery as librarians and doctors -- literary
critics and lawyers. I know engineers who'll go to
war over the difference between centripetal
and centrifugal force. Swing a rock on the
end of a string, and you can name the force in the
string by whether you regard it as pulling on the
rock or pulling on your hand.
I do that with the word heat. I cringe when
someone says that a teakettle contains heat. Heat
is what we call the energy flowing from the stove
to the kettle. Once in the water, it becomes
internal thermal energy. That nicety is
useful when we write energy balances, but it's of
precious little use in the world at large. A
dentist talks about the lingual and
buccal sides of a tooth -- more terms that
few of us need. You and I simply add a few words.
We refer to the side of the tooth facing into, or
out of, the mouth.
It should all come down to practical utility. When
a dentist and technician spend the day locating
flaws in peoples' teeth, a word like buccal saves a
lot of time. But trying to name every thing in the
world would clutter language unbearably.
Years ago, I had a wise, but
quirky, professor who was death on verbal
clutter. When he came to the ratio of transport
properties called the Prandtl Number, he
avoided the term. He just squandered two extra
words and named the properties. That way, students
never got the ratio wrong.
Writing for radio exposes how needless specialized
language can be. If we really understand what we
mean to say, we can find our way back to plain
English. Rarified language makes a fine shield when
we're uncertain. Take the word quotidian. In
medicine, it means daily or
recurring. But it can also mean common,
everyday. When I hear someone use it that way,
I know I'm being warned not to question. I'm being
told that nothing is common, or flawed, about
anyone grand enough to use that uncommon
word.
So, when I think I have a new idea, I remind myself
that I have to put it in words that we all
understand. If I can't, I need to keep working. No
idea is ever within our grasp until we can tell it
in words that we all understand.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
The UH Reference Librarian was Dr. John E. Fadell,
linguist and source of limitless word lore. I am also
grateful to the good people in the office of Dr.
Phyllis Morgan, who, while they work on my teeth,
willingly tell me what their words mean. The on-line
library discussion group is ExLibris.
Just for the record, the Prandtl Number, Pr,
is the viscous diffusivity divided by the thermal
diffusivity. It helps one to see whether viscous
drag or heat flow is the dominant process in a
given problem.
Connecticut listener David Faile writes with one on
the more far-out naming stories. It turns out that
those removable strips of paper on the outside of
the old tractor-feed paper supplies were called
perfory. After this episode was first
aired (just before the 1999 presidential election)
another related term has become commonplace -- the
term chad. For a huge list of offbeat
terms, that includes perfory, but not
P-slip, click
here.

The Engines of Our Ingenuity is
Copyright © 1988-2000 by John H.
Lienhard.