Thinkers vs. Tinkerers, and Other Debates

Welcome to the fourth of our TIME 100 special issues profiling the hundred most influential people of the century. We began a year ago by picking 20 leaders and revolutionaries, followed by artists and entertainers, then business titans. Now comes our convocation of the greatest minds: this century's 20 most influential scientists, thinkers and inventors.

Among the most interesting debates we had, especially with our outside experts, were those concerning the relative influence of thinkers vs. tinkerers--those who work mainly inside their own mind vs. those who turn their mind to practical things. In some centuries the tinkerers are more influential. The 15th, for example, was important for Gutenberg building his printing press and Columbus setting sail; the 19th for Fulton and his steamboat, Morse and his code, Bell and his telephone, Edison and his light bulb. But in other centuries the pure thinkers were more influential. The 17th, for example, boasted Newton, Galileo, Descartes and Locke.

Our century had its share of great thinkers. Einstein, most notably, was the greatest theorist since Newton, whose universe he overthrew. Einstein's ideas led to making the 20th a century of physics, one marked by manipulations of subatomic particles in ways that produced everything from atom bombs to silicon chips.

The other great theoretical breakthrough of this century was the discovery by James Watson and Francis Crick of the self-replicating structure of DNA. Their thinking may make the 21st century a century of biotechnology, one marked by the manipulation of DNA in ways that produce everything from customized drugs to human clones.

But our century will also be remembered for its brilliant tinkerers. The ability to transcend gravity, brought about by folks from the Wright brothers to Robert Goddard, affected the way we live as much as Einstein's ability to figure out what gravity actually is. Philo Farnsworth's ability to turn electrons into television images was likewise as influential as figuring out what electrons actually are. Indeed, our century may be noted most for those who went out to their garages (metaphorically, at least) and helped bring us televisions and transistors, plastics and penicillin, computers and the World Wide Web.

Often it was hard to pick one person to credit for a particular advance. Some cases involved famous rivalries, such as Farnsworth vs. Vladimir Zworykin over inventing television, or Jonas Salk vs. Albert Sabin over developing a polio vaccine. Other cases, such as the creation of the atom bomb or the computer, involved a series of contributions. Although there is a danger in personalizing history, there is also an advantage. By choosing the people we feel were most responsible for key breakthroughs, and then exploring their relations and rivalries, we hope to convey the human excitement that makes real the progress of science. We created two gatefolds--a time line of the century's discoveries (page 109) and a chart of how computing and communications converged (page 141)--as a reminder that great thinking is part of a continuous group endeavor.

Telling the story of science and invention through people has always been part of TIME's mandate. In 1923, our first year, we did a cover on Frederick Banting, who helped isolate insulin, and the following year we did covers on Sigmund Freud and Leo Baekeland, who both made it onto our list this week. Science and technology have been particular interests of mine: this is the 40th cover related to these fields that we've done since I became managing editor 40 months ago.

The TIME 100 series has become a true multimedia project. A CBS News special hosted by Morley Safer will air this Thursday, March 25, at 10 p.m. E.T. A panel with some of our experts was moderated by Charlie Rose for his pbs television show, which airs Monday, March 22. We have a place on our website

) where you can express your own opinions. cbs Radio has been broadcasting short profiles on each selection. A book series is available (800-692-1133), and we are hoping to produce a coffee-table volume for Christmas. And Madame Tussaud's wax museum in London has just mounted an exhibition of our selections.

Our next and last TIME 100 issue, looking at the heroes and icons who shaped our century, comes out this summer. Then we'll begin the daunting task of picking a Person of the Century. Comparing the impact of scientists with that of artists, leaders and heroes will be difficult. Even with the luxury of historic hindsight, it's hard to gauge who had the most effect. (Pop quiz: Who had more lasting influence in the 16th century, Shakespeare or Martin Luther, Magellan or Michelangelo, Elizabeth I or the Mogul leader Akbar?)

We realize there are no right answers. But we do believe that the process of thinking these questions through and hazarding an argument can be illuminating--and perhaps even enlightening. We welcome your suggestions.