Lack of imagination can stifle progress.

Those who believe they know how the information highway or other new technologies will shape the future should review a little history, maintains Nathan Rosenberg, an economist of technological change at Stanford University. Those who witnessed the birth of the telephone, radio, laser, computer, steam engine, VCR, and countless other inventions didn't always imagine their social and economic impacts accurately, he points out. In hindsight, the future was "obviously not obvious" to contemporaries of most major 20th-century inventions, he says. Consider these failures to anticipate the future uses and markets for innovations:

* Western Union turned down the chance to buy Alexander Graham Bell's patent for a mere $100,000. The lack of enthusiasm that greeted the telephone most likely was rooted in the failure of the human mind to imagine a long-distance communications device that served more social purposes than those already served by the telegram.

* The jet engine, in 1940, looked like a dud to a committee of the National Academy of Sciences because it would have to weigh 15 pounds for each horsepower delivered, compared to slightly more than a pound each for internal combustion engines. "Within a year, the British were operating a gas turbine that weighed a mere four-tenths of a pound per horsepower."

* Electricity and lasers took decades to find major uses because both were newly discovered phenomena that did not represent an obvious substitute for anything that already existed.

* Ten to 15 orders was all IBM envisioned for the computer in 1949. Even by 1956, a Harvard University physicist involved in developing the machine for solving differential equations said he would be surprised if the billing departments of department stores ever could make use of such a number cruncher. The fact that early machines relied on 18,000 vacuum tubes and that the semiconductor had yet to be invented probably limited everyone's imagination.

* The future prospects for communication satellites looked bright in the early 1970s, but declined quite unexpectedly in the 1980s with the introduction of fiber optics cable. Fiber optics, meanwhile, has lost its lead in medical diagnostics, as newer visualization technology such as magnetic resonance imaging takes hold. These examples illustrate that "one of the greatest uncertainties controlling new technologies is the invention of yet newer ones," Rosenberg says.

The difficulties of applying technology help explain...