Recently, the author and literary agent John Brockman posed the question, "What is the most important invention in the past 2000 years?" He received thoughtful and often surprising answers from more than 100 leading thinkers, a fascinating survey of intellectual and creative wonders of the world.

Some people nominated inventions that were influential in bringing the world to where it is today, such as the printing press, calculus, the invention of the scientific method and effective contraception. Other interesting suggestions included anesthesia, plumbing and sewers, reading glasses, batteries, the concept of education, self-governance, and the notion that mathematics could be used to represent things.

Christopher Langton, a computer scientist, proposed the telescope, which "opened the doors to the flood of data that would resolve what were previously largely philosophical disputes."

James J. O'Donnell, professor of classical studies at the University of Pennsylvania, proposed modem health care — from antibiotics to medical techniques to the soap that doctors use to wash their hands.

Review your own life and imagine what it would have been like without late-20th-century heath care," he wrote. "Would you still be alive today? An astonishingly large number of people get serious looks on their faces and admit they wouldn't."

Douglas Rushkoff, a writer and teacher, proposed "the eraser. As well as the delete key, white-out, the Constitutional amendment, and all the other tools that let us go back and fix our mistakes."

Tor Norretranders, a Danish science writer, nominated the mirror, which became commonplace during the Renaissance. "Only with the installation of mirrors in everyday life did viewing oneself from the outside become a daily habit," he wrote. "This coincided with the advent of manners for eating, clothing and behavior. This made possible the modern version of self-consciousness: viewing oneself through the eyes of others, rather than just from the inside or though the eyes of God."

Howard Gardner, professor of education at Harvard University, proposed classical music. "Most inventions -- from nuclear energy to antibiotics -- can be used for good or ill," he wrote. "Classical music has probably given more pleasure to more individuals, with less negative fallout, than any other human artifact."

Other people nominated inventions for the promise they hold for the future. The computer, the Internet and biotechnology were leading candidates.

"The Internet will dissolve away nations as we know them today," wrote Clifford Pickover, an IBM researcher. "Humanity becomes a single hive mind, with a group intelligence, as geography becomes putty in the hands of the Internet sculptor."

Lawrence Krauss, who chairs the physics department at Case Western Reserve University, wrote: "While the printing press certainly revolutionized the world in its time, computers will govern everything we do in the next 20 centuries . . . The only other invention that may come close is perhaps DNA sequencing, since it will undoubtedly lead to a new understanding and control of genetics and biology in a way which will alter what we mean by life."

"Ultimately," added Robert Shapiro, professor of chemistry at New York University, "we may elect to rewrite our genetic code text, changing ourselves and the way in which we experience the universe."

Other nominations reflect seemingly simple things of life. Freeman Dyson, a professor of physics at Princeton, said hay was the most important invention. "In the classical world of Greece and Rome and in all earlier times, there was no hay," he explained. "Civilization could exist only in warm climates where horses could stay alive through the winter by grazing. Without grass in winter you could not have horses, and without horses you could not have urban civilization. Some time during the so-called dark ages, some unknown genius invented hay, forests were turned into meadows, hay was reaped and stored, and civilization moved north over the Alps. So hay gave birth to Vienna and Paris and London and Berlin, and later to Moscow and New York."

And Jeremy Cherfas, a biologist and BBC Radio Four broadcaster, nominated the basket: "Without something to gather into, you cannot have a gathering society of any complexity, no home and hearth, no division of labour, no humanity."

The entire list of nominated inventions is on the Internet at www.edge.org/documents/Invention.html. Reading them reminds me of how wondrous our world is.

Copyright 1999 by Bill Gates. Distributed by New York Times Special Features.