The Power Of Big Ideas

Was the light bulb more important than the pill? An online gathering of scientists nominates the most important inventions of the past 2,000 years. Some of their choices might surprise you.

WHAT CHANGED THE COURSE OF HUMAN events most profoundly? It wasn't a general or battle, emperor or president or assassin, as the ""Great Man'' school of history holds. It was more likely . . . well, clocks or hay, the thermos bottle or smelting or writing. It was, in other words, a technological invention, according to 80-plus scholars gathered in the electronic salon called Edge (www.edge.org). In November, literary agent and author John Brockman, who presides over Edge, asked scientists and other thinkers to nominate the most important invention of the last 2,000 years. In the postings being released this week, one theme emerges: while the absence of any single political event would not have changed history much (if Gavrilo Princip hadn't shot Archduke Francis Ferdinand to start World War I, something else would have), the absence of certain inventions would have produced a world far different from the one we inherited. Without the automobile, there would be no suburbia.

Some of the Edge offerings are predictable (the steam engine, the telescope, space travel); some suggest that their nominators should log off occasionally (the Internet, public key encryption). Others are provocative: batteries, notes philosopher Daniel Dennett of Tufts University, allowed the development of transistor radios and cell phones, which are ""the most potent weapons against totalitarianism ever invented, since they destroy all hope of centralized control of information.'' Even an invention as simple as knitting, argues physicist Freeman Dyson of the Institute for Advanced Study in Princeton, N.J., triggered changes. Before knitting, many children died over the winter, so parents did not dare invest emotionally in them. The warmer clothes made possible by knitting ""freed parents to develop a loving relationship with their children,'' says Dyson. Together, the nominations make a strong case that how we think, and the social and political institutions we create, are products of the science and technology we invent.

READING GLASSES Simple pairs of spectacles, says psychologist Nicholas Humphrey of the New School for Social Research in New York, ""have effectively doubled the active life of everyone who reads or does fine work--and prevented the world being ruled by people under 40.'' That alone gets them into the inventions pantheon, but glasses also foster the mind-set that people need not accept the body nature gave them, and that physical limitations can be overcome with ingenuity.

THE ATOMIC BOMB With the destruction of Hiroshima and Nagasaki in 1945, mankind demonstrated that it had forged a technology that could, in seconds, return civilization to the Stone Age. Forever after, with or without a cold war, we will live in the shadow of the mushroom cloud.

THE PRINTING PRESS Among Edge's 80-plus postings, Gutenberg's 15th-century invention of movable type won by a landslide. The printing press allowed, for the first time, the rapid and widespread dissemination of information, knowledge and scholarship. It not only made myriad other inventions possible, since most inventions build on accumulated knowledge, but also triggered profound and lasting social and political changes. The printing press ""led directly to mass literacy [and] democracy,'' notes Hendrik Hertzberg, executive editor of The New Yorker. Agrees physicist Raphael Kasper of Columbia University, ""It spread knowledge beyond a small number of privileged individuals, thus permitting larger numbers to share or debate world views and to build upon past and present ideas.''

CLOCKS Timepieces allow the practice of science, which is filled with quantities such as cycles per second. More important, they induce what W. Daniel Hillis, the father of massively parallel computing and vice president of R&D at the Walt Disney Co., calls the ""temperament'' of science. The clock, he says, embodies ""objectivity. It converted time from a personal experience into a reality independent of perception. It gave us a framework in which the laws of nature could be . . . quantified.'' Clocks also offer a metaphor for the unfolding of natural law--""God as watchmaker,'' winding up creation and letting it run--that lay the foundation for scientific thinking.

PLUMBING Waterworks, the plumbing and sewers that carry clean water to homes and fields and dirty water away from them, allowed cities to develop, argues Carl Zimmer of Discover magazine. ""Without waterworks, the crowded conditions of the modern world would be utterly insupportable,'' he says. Waterworks allow microbial diseases such as cholera to be controlled, promoting public health, and let agriculture bloom in arid regions from the Middle East to California, shifting entire economies.

THE STIRRUP Historian Lynn White argues that the stirrup revolutionized warfare and made feudal society possible. With the Magna Charta, feudalism led to the idea of the consent of the governed. Keeping to the equine theme, Freeman Dyson nominates hay, without which civilization could not exist in northern climates. ""Without horses you could not have urban civilization,'' he says. ""So hay gave birth to Vienna and Paris and London and Berlin.''

NUMBERS What does 3,780 have that MMMDCCLXXX lacks? Place value, thanks to the Hindu-Arabic number system, in which the position of a digit conveys information about its value. Combined with the use of a symbol for zero, the number system allows modern mathematics and hence science and technology, argues neuroscientist V. S. Ramachandran of UC, San Diego. Without it, says mathematician Keith Devlin, ""Galileo would have been unable to begin the quantificational study of nature that we now call science. Today, there is scarcely any aspect of life [including computers] that does not depend on our ability to handle numbers efficiently and accurately.'' Calculus, invented independently by Isaac Newton and Wilhelm Leibniz in the 17th century, builds on this number system. Modern technology might have arisen 1,000 years earlier if the Greeks had invented calculus, suggests computer scientist Bart Kosko.

ERASERS AND DELETE KEYS Along with ""Wite-Out, the constitutional amendment and all the other tools that let us fix our mistakes,'' says Douglas Rushkoff, author of ""Cyberia'' and ""Media Virus,'' these inventions give us the ""ability to go back, erase and try again.'' Without it, ""there would be no scientific model,'' for science is predicated on the notion that all ""Truths'' are merely tentative, ready to be overturned by the next discovery. Nor, without erasers and their cousins, would there be ""any way to evolve government, culture or ethics,'' says Rushkoff. ""The eraser is our confessor, our absolver and our time machine.''

BIRTH CONTROL PILL The pill stimulated ""feminism and the consequent erosion of conventional family structure in Western society,'' says Oxford University neuroscientist Colin Blakemore, and also fostered ""the beginnings of an utterly different attitude to the social role of women.'' But arguably its most important effect, he suggests, was ""the growing conception that our bodies are servants of our minds, rather than vice versa.''

CLASSICAL MUSIC Works like Beethoven's, with their exquisite orderliness and beauty, have influenced ""other forms of cognition,'' suggests psychologist Howard Gardner of Harvard University. According to the theory of the ""Mozart effect,'' classical music fosters spatiotemporal thinking--the kind that underlies logic and math. Besides, says Gardner, ""the pleasures of classical music are so widely available and cause so little damage.''

THE COMPUTER Forests are felled so the digerati can write paeans to the power of processors to change the way we live, but computers can also save civilization itself, says neurophysiologist William Calvin of the University of Washington. Global climate is changing under the onslaught of greenhouse gases (from burning coal, oil and natural gas). Only computers, Calvin argues, ""may allow us to understand the earth's fickle climate'' and thus ""prevent a collapse of civilization.'' If computers save us from ourselves, they will also ""govern everything we do in the next 20 centuries,'' says physicist Lawrence Krauss of Case Western Reserve University. They will push ""the next phase of human evolution,'' he predicts, with self-aware, self-programmable computers becoming ""integrat[ed] into [our] own development.''