I've said many times before: 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.

A friend has been scolding me about the introduction you just heard. He asks, "What's this series about?" What do I mean by "the machines that make our civilization run"? I talk about biology and poetry right along with steam engines and airplanes. Do I use the words "engine" and "machine" too broadly?

The fact is, I've run awash in the fluidity of our language. The words we speak constantly find new meanings that blur the old. But the ghost of old meaning lingers. Buy an air coach fare, and an old echo rings in your mind. It is the clatter of horses and the rush of cold night wind past your carriage.

That's why the title of this series, The Engines of Our Ingenuity, can be confusing. Those words have changed. So I get mail addressed to "Engines of the Mind" and "Ingenue's Engines."

Actually, my title is a pun. Engine and ingenuity both come from the same Latin word, ingenium. It means innate mental power. Engine is one more word that's changed on us. It used to mean any product of our mind. We're getting back to that meaning today. A search engine is software that seeks out information. That's a long way from the engine under the hood of your car.

Chaucer once said that our wisdom takes three forms. They are "memorie, engin, and intellect." By memorie and intellect he meant the same things we do. But by engin, he meant creative right-brain wit. He meant invention. So did Sir Walter Scott when he told about "A man of quick ingine and deep wisdom."

The word machine is like that. It means any device that carries out a function -- like the machinery of government.

The architect Le Corbusier called a dwelling a "machine for living." Huxley did him one better. He called King's College Chapel "the perfect machine-for-praying-in."

We get the word machine from Greek theatre. Mechanical ropes and pulleys delivered the deus ex machina. He was the rescuing god who inserted a happy ending into a hopeless story. Our machinations are the ingenious ways we make things come out the way we want them to.

There's an odd message in all this. Our machines are never far from ourselves. We are what we make. The machine, after all, is born in the ultimate engine. And that is our ingenuity.

So my friend is right. The words machine and engine have narrowed down. They've grown small. Once those words linked the mind that creates things to the things themselves.

Our ingenuity is the real engine. The rest -- art and technology, science and literature -- they are shadows cast by greater machines -- by the machinery of our minds.

I'm John Lienhard, at the University of Houston, where we talk about the way inventive minds work.

(Theme music)

See entries under machine, engine, ingenuity, and genius in the Oxford English Dictionary, 2nd ed. (J.A. Simpson and E.S.C. Weiner, eds.). Oxford: Clarendon Press, 1989.

For an earlier discussion of the etymology of the words with which we talk about science, engineering and technology, see Episode 12.