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No. 57:
The Samurai Sword

Today let's talk about ceremony and technology. 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.

My grandmother to tell me that if I burned my finger, I should dip it in a cup of tea. She knew that, long before doctors knew anything about the healing power of the tannic acid in tea. Now my grandmother was a fine intelligent woman, but she didn't know organic chemistry.

The art of Japanese Samurai sword making is like that. It reached an astonishing level of perfection as early as 800 AD -- 1200 years ago. A Samurai sword is a wonderfully delicate and complex piece of engineering. The steel of the blade is heated and folded and beaten -- over and over again -- until the blade's formed by 33,000 layers, forge-welded to one another. Each layer is a hundred thousandth of an inch thick. All this is done to extremely accurate standards of heat treatment. The result's an obsidian-hard blade with willow-like flexibility.

These blades represent a perfection of production standards that modern quality control hasn't matched. Yet the Japanese craftsmen who made them didn't know anything about temperature measurement or the carbon-content of steel. How do you suppose they repeated such perfection?

The answer's one we'd be well advised to remember. Sword making was swathed in ceremony and ritual. It was consistent because the ceremony was precise and unvaried. The ceremony was beautiful -- in action, dress, and color. Heat treating temperatures were controlled by holding the blade to the color of the morning sun. The exact hue was transmitted from master to apprentice down through centuries. Sword-making was a part of Japanese art; and it was subsumed into Japanese culture.

That sort of thing wasn't unique to the Japanese. It was true of 18th-century violin-making and 12th-century cathedral building. Ritual did what was later done with weights and measures.

Our intelligence, after all, runs deeper than a mere ability to read gages. Our great technologies arise out of a full range of experience. They come from creativity that's triggered by more than tables of technical data. Good technology isn't independent of culture. The best doctor knows organic chemistry and his grandmother's folklore. The best metallurgist knows about iron-carbon phase diagrams and medieval Japanese craftsmanship.

The best engineers know mathematics, physics, and thermodynamics. But they also know the world they live in. The best engineers have a deep-seated knowledge of the people they serve.

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

(Theme music)

The ideas about ceremony and technology are developed nicely by Bronowski, J., The Ascent of Man. Boston: Little, Brown and Company, 1973, 1973, Chapter 4, The Hidden Structure. This is also available on videotape and film.

For more on Japanese swords see, Sato, K., The Japanese Sword (tr. by Joe Earl). Tokyo, Kodansha International Ltd. and Shibundo, 1983.

This episode has been revised as Episode 1384.