Can an inventive society get bolder as it grows older? That question affects people of all ages – especially those living in the United States, Europe, and Japan, which are expected to have fewer workers supporting more retirees.

According to Science and Engineering Indicators: 2002, issued by the National Science Board (NSB), an independent legislative and executive advisory body established by the U.S. Congress in 1950, America’s science and engineering workforce will continue to grow in coming decades, but its average age is likely to rise. Will scientific workers in their 50s and 60s continue to make valuable contributions?

The report avoided asking whether aging impairs creativity. If it does, then the growth of our productivity and improvement of our standard of living might be in trouble. There is already a shortage of young Americans in research; in 2003 the NSB expressed concern over the United States’ dependence on foreign PhDs.

Scientists, often older ones, have for years questioned how long they can stay productive. G. H. Hardy set the tone in his 1940 classic, A Mathematician’s Apology. “Like any other mathematician who has passed sixty,” Hardy confessed, “I have no longer the freshness of mind, the energy, or the patience to carry on effectively with my proper job. “He continued that “mathematics…is a young man’s game.”

The age lore of other sciences can be similarly misleading. The Nobel laureate physicist Paul Dirac has suggested, tongue in cheek, that a physicist over 30 was as good as dead, and the physicist-historian Abraham Pais wrote of Einstein after 1925 (when Einstein was 46) that, as far as his work went, he might as well have gone fishing. And yet the sociologist Harriet Zuckerman, in her landmark 1977 book, Scientific Elite, observed that U.S. Nobelists received their prizes for work done when they were, on average, nearly 39. Sir Nevill Mott won a Nobel in physics for his postretirement research.

Great biologists seem especially hardy. The German naturalist Alexander von Humboldt successfully surveyed harsh, remote areas of the Russian Empire for goldfields after turning 60, and began publishing the 19th century’s greatest work of synthesis, Cosmos, at age 76; he had completed 2,000 pages by his death at 89, in 1859. More recently, Harvard University’s Ernst Mayr was still writing papers at 100.

Why, then, do certain researchers stagnate while others flourish? Some might be internalizing what Zuckerman called the “mythology” of aging in science. But another factor is that any education has built-in limits. Even Einstein may have been bumping against them. Scientists over 40 face a choice: continue using the endowments that have served them well but are challenged by a new generation, or turn to new subjects.

Thus Humboldt – who had earned his fame in the tropics – turned to the bleak North. In his early 50s, Wilhelm Ostwald resigned his chair of physical chemistry at the University of Leipzig to pursue philosophy, color theory, and the promotion of scientific knowledge. He is honored not only for the chemical discoveries that led to his Nobel Prize in 1909 but for his work on an early version of the hypertext concept.

For engineering and invention, the implications of an aging brain trust are quite apparent. There, too, young people are responsible for many basic innovations. But that doesn’t mean they will stagnate as they age. Thomas Edison was in his late 60s when he developed the disc phonograph. Shumpei Yamazaki of Japan, the inventor of flash memory, has at 62 just displaced Edison in the Guinness book of records, after pointing out that his 3,245 patents exceeded Edison’s 2,332. Othmar Ammann designed New York’s Verrazano-Narrows Bridge in his late 70s; the Swiss engineer Christian Menn completed the revolutionary cable-stayed Zakim Bunker Hill Bridge in Boston at 75.

What is the secret of such men and women? Partly, it is that they do not expect the flashes of mathematical insight that may indeed be the prerogative of the plastic youthful brain, but instead forge new syntheses aided by experience.

For some, this drawing on experience can become an ever renewing source of inspiration. Germany’s most prolific patenter, Artur Fischer, made a breakthrough as a young man in 1948 with Germany’s, and perhaps the world’s, first electrical system for triggering a photographic flashgun automatically when the shutter is released. He then applied his research on plastic parts in projection screens to the development of a bestselling nylon wall anchor for the building trades, millions of which are still made daily by the firm he founded. The principle of this plastic-sheathed bolt in turn became a key element in his line of model-building kits, Fischertechnik, which is used by industrial prototypers as well as schoolchildren. At 85 he has developed a system for making biodegradable toys from potato starch.

As Fischer has aged, the markets for his ideas have grown younger. To attract more kids to invention, it might help to show them that talent has no expiration date.