Success through Failure

The Paradox of Design

Henry Petroski

• Publisher: Princeton University Press
• Year: 2018
• ISBN:
  9781400889686
• Topic: Conception
• Subtopic: Conception industrielle

From the acclaimed author and engineer, an engaging and lively account of the surprising secret of great design Design pervades our lives. Everything from drafting a PowerPoint presentation to planning a state-of-the-art bridge embodies this universal human activity. But what makes a great design? In this compelling and wide-ranging look at the essence of invention, distinguished engineer and author Henry Petroski argues that, time and again, we have built success on the back of failure—not through easy imitation of success. Success through Failure shows us that making something better—by carefully anticipating and thus averting failure—is what invention and design are all about. Petroski explores the nature of invention and the character of the inventor through an unprecedented range of both everyday and extraordinary examples—illustrated lectures, child-resistant packaging for drugs, national constitutions, medical devices, the world's tallest skyscrapers, long-span bridges, and more. Stressing throughout that there is no surer road to eventual failure than modeling designs solely on past successes, he sheds new light on spectacular failures, from the destruction of the Tacoma Narrows Bridge in 1940 and the space shuttle disasters of recent decades, to the collapse of the World Trade Center in 2001.Petroski also looks at the prehistoric and ancient roots of many modern designs. The historical record, especially as embodied in failures, reveals patterns of human social behavior that have implications for large structures like bridges and vast organizations like NASA. Success through Failure —which will fascinate anyone intrigued by design, including engineers, architects, and designers themselves—concludes by speculating on when we can expect the next major bridge failure to occur, and the kind of bridge most likely to be involved.

1

FROM PLATO’S CAVE TO POWERPOINT

Should we not illustrate our lectures, and cease to lecture about our illustrations?

—C. H. TOWNSEND¹

Imagine anyplace, anytime. There, on a cloudless night, the shadows cast by a full moon light the landscape as if it were a stage. A quiet and patient observer could watch the limned images of wildlife morph out of the wings and stalk and flee in pantomime, playing out a nightly drama under the stars. As the moon progresses across the sky, the shadows on the ground slowly but inexorably follow their own circuit, shortening and lengthening around the moondial. At dawn, the footlight of the sun signals a new act.

From the beginning of the solar system, the stage has been set for such dramas in light and shadow. Given that, they are unremarkable. Yet the unremarkable often serves as the basis for the remarkable. Any light will, of course, cast shadows. Fire, being a flickering source, can introduce an added eeriness and nervousness to the camp theater in the round, the shadow players thrown back as it were from the heat. For millennia, our ancestors passed nights by the light of flames keeping an audience of wildlife at bay.

Daylight produced an inversion of the set—and views we have all on occasion seen were created “entirely independent of man’s invention and control.” In a room darkened by shutters against a bright sun, the wall opposite can display a sharp inverted image of an outdoor scene. A distant grazing cow, perhaps, or a floating cloud, can be carried on light squeezed through a hole in the woodwork like water through a small breach in a tank. Likewise, on the shaded ground beneath a tree, an image of the sun can be thrown down through “chinks between the leaves.” These are perfectly natural phenomena that take no lens or sleight of hand to produce.²

More often than not, however, what we see projected is the product of design. Plato’s allegory of the cave makes much of a controlled drama of illumination and images. In the dialogue with his young follower Glaucon, Socrates describes prisoners who have lived since their childhood in a den, where they sit with their backs to the entrance and are restrained so that they can look only at the wall directly in front of them. Behind them, fires burn and provide a source of light. Between the prisoners and the flames there is a raised walkway, and anything that moves across it casts a shadow on the wall. To the prisoners, these shadows are the extent of their experience and so become their reality.³

After describing the situation in the cave, Socrates posits that one of the prisoners be set free and be allowed to turn toward the mouth of the cave and see the fires and also the players and their burdens that have been casting the shadows. Which will be more real to the freed prisoner, Socrates asks, what he now sees in the flesh or what he has seen as shadows all his life? And if the prisoner is forced to look directly into the source of light, Socrates asks further, will he not be blinded and wish to turn back toward the wall of the cave, where images are sharper and more familiar?

Socrates then imagines that the prisoner is taken out of the cave and exposed to the direct experience of the sun and everything that it illuminates. At first the prisoner would be blinded by the brightness, but in time he would come around to see the world outside the cave for what it is. If he then returned to the cave and sat among the prisoners who had remained there, his descriptions of the sources of the shadows and external reality would be met with skepticism. Better to remain in the cave, the prisoners would say, rather than to go away and come back without clarity of vision.

Great philosophical and technical advances have been made since ancient times, with varying contributions to understanding reality and capturing it in media more tangible than shadows. The camera obscura enabled artists to capture fleeting glimpses of reality undistorted and in proper perspective, albeit upside-down. David Hockney has argued that Renaissance painters employed such technology to produce their almost “photographic” masterpieces.⁴

The use of chemical fixing to freeze images in the optical camera—which photography pioneer William Henry Fox Talbot referred to as “the pencil of nature”—made it possible to stop the wings of birds in flight, the tails of cats in free fall, and the hoofs of horses in full gallop. This technological development and its consequent mechanical realism paved the way for nonrepresentational modern art. Now, digital imaging has made it possible to graft the head of a lion onto the body of an eagle, providing evidence for the existence of griffins, if we can believe our eyes.

Developments in optics, chemistry, electricity, and computers have at the same time freed us from Plato’s cave and shackled us within another. The allegory of the cave updated to modern times might be set as follows. A group of people is seated in a cavernous room, restrained by a prevailing paradigm. The chairs in which they sit are rigidly attached to the floor and to each other, and images on the screen before them rivet the group’s eyes to it. They are watching things that are being projected from a booth in the back of the room, which they sometimes forget they are in. On occasion, a head casts a shadow on the screen, and members of the group move slightly to check if it is theirs. The images on the screen are accompanied by commentary coming from a disembodied voice issuing from speakers distributed around the room. Now and then a red dot moves about the images, like a fly about a horse, and lights upon a point. The voice continues to describe the images and read the words projected on the screen. The images and words are sharp and bright and are the reality of the moment. They fade in and fade out like shadows on a night of patchy clouds.

This modern Plato’s cave could obviously be an auditorium in which a PowerPoint presentation is being made. PowerPoint is, of course, the computer program produced and marketed by Microsoft, but it is also a thing, in the sense that it was invented and has been designed, and redesigned—by maker and user alike. It continues to evolve with ever more bells and whistles and ever more clever new uses. However, unlike a bottle cap or an umbrella, this thing is not something we can grasp in our fingers or hold in our hand. It is intangible. It is not hardware. It is software, designed for use within a system of computers and projectors and screens and speaker and audience. PowerPoint is a thing that enables its user to accomplish an end, namely, the design of a “slide show,” which is also a thing of sorts. Thus the language of PowerPoint, like the language of everything made, harks back to some previous thing, for long before there were digital computers, there was a need to communicate visual images to an audience in such a manner that the images could be viewed simultaneously by everyone present.

Among the oldest surviving permanent works of art are drawings on the walls of caves in France, India, and elsewhere around the world. These cave drawings may have been made not strictly for aesthetic reasons but as illustrations and schematic diagrams before which gathered novices could be instructed by elders in the art of war, or before which hunting parties could be briefed on strategy prior to departing on a sortie. It has been speculated that ancient petroglyphs found in California were drawn to record earthquake activity in the area.⁵ Perhaps these primitive rock paintings also served to assist in communicating the nature of and the responses to earthquakes.

Stone carvings and inscriptions are as old as civilizations. Among surviving hieroglyphics are depictions of how heavy statues were moved, diagrams of obvious instructional value for a team of haulers assembled before them. Obelisks have been inscribed with diagrams showing how they were erected. Likewise, inconspicuous stones and timbers found in vaults, attics, and other less accessible places in Gothic and medieval structures have revealed the sketches and calculations of stonemasons and carpenters—perhaps merely scratched out to clarify their own thinking or drawn for the instruction of an apprentice. To this day, it is not uncommon to find such essaying or instructional graffiti on furniture or at building sites.

Venues for formal and informal education have long been places where visual aids have been employed. As recently as half a century ago, blackboards were standard equipment in classrooms and lecture halls, and many teachers and professors prided themselves in their board work. But blackboards, like all made things, had their limitations, among which were the propensity to get dusty after too many erasings and the difficulty of being read in less than ideal light. So-called white boards, which were often touted as successors to blackboards, became common in the latter part of the twentieth century. The multicolored pens that were used with white boards were ostensibly a great improvement over chalk, which is notoriously brittle. Unfortunately, white-board pens emit distracting if not intoxicating fumes and tend to dry out, leaving a mark too faint to be easily seen.

Not every lecturer was able to develop a facility with writing and drawing on a black- or a white board. Though some prided themselves in their (usually well-practiced) ability to produce Palmer-quality penmanship on the vertical surface of a board, most could not even keep their lines level or their inclines parallel. Drawing was especially difficult for many a nonartist, which was a considerable liability for a naturalist or architect attempting to construct an accurate image of flora, fauna, or facades. Hence, any device that could be employed to project drawings made carefully at one’s leisure, or pictures cribbed from nature or from sources with access to better draftsmen or, at later times, photographers, would have been enthusiastically welcomed. However, according to one historical survey of optic projection,

No one knows who first designedly arranged a darkened room with a white wall or screen on one side, and on the other a small opening facing some object or scene that could be brightly illuminated. All we know is that the earliest accounts of the pictures in a dark place are in connection with the explanation of some other phenomenon, and not to show that such pictures were possible. It was also recognized in the first statements, as in the works of Aristotle and of Euclid, that [just] as light rays extend in straight lines, … those from an object must cross in passing through a small hole, and hence the images beyond the hole in the dark place must be inverted, the top being below and the right being left.⁶

The problem of projection was thus not new even in ancient times, and neither were solutions in the Middle Ages. The camera obscura, or “dark chamber,” though not necessarily by that name, was described as early as the eleventh century⁷ and was mentioned by Leonardo in the late fifteenth.⁸ It was embodied in the principle of a pinhole in one wall being the source of an inverted image projected upon the wall opposite. Using an artificial light source in place of the sun would have enabled images to be cast upon a wall even at night. As early as the fifteenth or sixteenth century, Sicilian priests were reported to be “using lanterns of undescribed construction with hand-painted slides” to produce visions.⁹ Since visions tend to be ethereal anyway, the quality of the projected image need not have been very sharp to be effective. Giambattista della Porta, whose Magia Naturalis appeared in the mid-sixteenth century, first described using “a convex lens to perfect the images and of placing transparent drawings opposite the opening.” Furthermore, “To these drawings he attached movable parts, and thus produced astonishing effects, which the unlearned ascribed to magic, a term connected with the lantern ever since.”¹⁰ (In the mid-nineteenth century, after photographic slides began being used in the “magic lantern,” one lecturer would wish “that some more scientific, if not so familiar, a name for our instrument were recognised.”)¹¹

In the seventeenth century, improved versions of the laterna magica were developed and used by physicians, mathematicians, and natural philosophers, including Johannes Kepler and Christiaan Huygens, who is often incorrectly credited with the invention of the magic lantern in the 1650s.¹² Naturally, the light source was a critical component of the projector, and “an elegant version” incorporating “a polished tin cylinder holding a concave mirror and candle” was made in 1671 by Athanasius Kircher. During the eighteenth century, the magic lantern—also to be known as a sciopticon or stereopticon—was used to amuse children. Later, entrepreneurs “employed the device to produce optical illusions for the deception of spiritualistic groups.” These illusions were principally phantasmagoria,¹³ a term that came to mean an elaborate display of optical illusions and effects by which “terrific figures are produced, which seem to approach the audience from an amazing distance and then recede again; or they rise to the ceiling apparently, and then descend to the floor.”¹⁴ Such uses of a hidden hand-held version may have earned the magic lantern the label “the lantern of fear.”¹⁵

An early magic lantern was illustrated in the second edition of Athanasius Kircher’s treatise on light and shadow. (From Ars Magna Lucis et Umbrae, 1671.)

In the nineteenth century, the basic magic lantern was typically made of tin, had an oil lamp inside, and was fitted with a chimney through which the smoke was carried away. A lens or set of lenses, known as “bulls’ eyes,” were placed in front of the source of light to diffuse it uniformly as well as to project whatever object or image was placed in its path.¹⁶ Though oil lamps may have been adequate sources of illumination for seances or small shows, better ones were desirable for scientific lectures and large extravaganzas. Early in the nineteenth century, the American chemist Robert Hare “discovered that a flame of oxygen and hydrogen blown against lime rendered it incandescent, given a dazzling light,” which came to be referred to as limelight. English inventors adapted and developed the phenomenon to the point where Henry Langdon Childe “projected his pictures on huge screens in the largest halls of London.” His use of “dissolving views” in conjunction with limelight, which he would employ in his “Grand Phantasmagoria” on the occasion of the 1838 opening of the London Polytechnic Institute, “became an essential part of lantern projection” from the mid-1820s through the end of the century.¹⁷ By the early twentieth century, smaller magic lanterns were “much in vogue for Christmas presents.”¹⁸

Although popularly developed as an entertainment medium, by which patrons could watch a picture show for a fee, ultimately mag...