Today, your host learns a lesson. 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 sit in an airplane on the way back from a speaking engagement. I'm trying to sort out an odd transaction. I talked about inventiveness. I told stories about eccentric creative people -- like the one about Einstein using the same soap for washing and shaving because using two soaps made life too complicated. I said that strange stories follow inventive people around, because invention itself parts company with normality. Invention is revolution. Invention is a trip into an uncharted land. Invention is eccentricity. It can be no other.

Afterward, a bright young man asked, "Do you mean I can't be inventive and still live a normal life?" It was an ingenuous question, but one I couldn't take lightly. It was one of those questions that someone asks when he isn't looking for information. This fellow saw the issues with perfect clarity. I felt in my bones that he'd voiced the question because he hoped he could get a new answer. He was like the person who goes back again and again to the opera hoping that, just once, Don José will have the sense to walk away from Carmen.

All that made the man's question difficult and dangerous. He so clearly wanted to be let off the hook. He wanted the brass ring without reaching into space to get it. He didn't want to risk humiliation. He didn't want to step off into the void.

I took a deep breath and answered. I said, "You cannot be inventive and live a normal life." Oh, I knew that you can live a normal life, at least in the outward markers of normalcy. But at some point you have to go where others haven't gone.

For some time Coleridge's Kubla Khan poem has been bouncing around in my mind. For several verses Coleridge tells of Xanadu, the "stately pleasure dome." But then he suddenly breaks off -- stops short as though he'd suddenly been invaded. He wheels full face upon us and, in one last disjunct verse, cries out a warning to us. He tells his vision of the creative daemon rising out of his own creative, troubled dreams. He says,

I would build a dome in air,
And all should cry, Beware! Beware!
His flashing eyes, his floating hair.
Weave a circle round him thrice,
And close your eyes with holy dread,
For he on honeydew hath fed,
And drunk the milk of paradise.

That man in the audience saw what other people in the audience didn't see. He understood why he should "close his eyes with holy dread" at the idea of drinking the creative milk of paradise. He knew what the inventive genie could do for him once it got out of the bottle. But he'd also caught a glimpse of the size and power of the beast.

He asked the question again on the way out of the building. He knew what was at stake. It bothered him. Now as the airplane circles into Houston, it is I who am bothered. He reminded me that creativity is too large a thing to be taken lightly.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

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