* She tamed cyberspace
Esther Dyson, 51
Chairman, EDventure Holdings
Often called "Queen of the Internet," Dyson is the computer industry's premier power broker and soothsayer. Her early vision of the Web as an entity free of governmental controls set the tone for the Internet we use today. "People don't understand that all that's on the Internet is other people," Dyson says. Her newsletter, Release 1.0, is required reading for the world's digital elite ("What she writes is what I care about," Bill Gates has said), and for 26 years the industry's heaviest hitters have schmoozed at her exclusive annual PC Forum conference.
* He leads the charge against AIDS and bioterror
Anthony Fauci, 62
Director, National Institute of Allergy and Infectious Diseases (NIAID)
In 1988, angry activists—protesting the federal government's slow response to the AIDS crisis—demonstrated outside Fauci's office, branding him a "murderer." The NIAID director responded not by having them arrested, but by inviting them in. And, he recalls, "to my amazement and gratification, they made an incredible amount of sense." Fauci joined with them to make unprecedented demands on the Food and Drug Administration, including early access to experimental drugs. Since then, he has also devised treatments for several formerly fatal vascular diseases.
"He's the greatest science administrator, combining both scientific leadership and science, that I have ever seen," scientist Robert Gallo has said. These days, Fauci's institute is boosting the supply of smallpox vaccine and testing Ebola and anthrax vaccines. "I don't see retirement on the horizon," he says.
* He proves that heaven can wait
Caleb Finch, 63
Professor of Neurobiology and Gerontology, University of Southern California
In the 1960s, Nobel laureate Peyton Rous confronted Finch, then a grad student investigating the process of growing old. "Why are you wasting your time on that?" Rous asked. "Everyone knows that aging is mainly about cancer and vascular disease!" But Finch was not swayed: "I had already convinced myself to the contrary." Finch revolutionized gerontology by showing that the aging process can be delayed. Among other advances, he has shown that low-calorie diets can slow brain aging in lab rodents.
You must remember this: In 2001, Finch revealed that the early stages of Alzheimer's may not involve cell death—opening the possibility that its ravages might be reversed.
* He starves cancer cells
Judah Folkman, 70
Director of Surgical Research, Children's Hospital, Boston
When Folkman first published his theory in 1971 that cancerous tumors create their own blood vessels, skeptics howled. "It would be like announcing today that you figured out how to do a head transplant," he has said. But Folkman's research silenced his critics. Knowing how tumors supply themselves with blood, scientists now work on shutting down the supply. Two dozen drugs based on his discovery are now in clinical trials.
Soul man: "My father was a rabbi, and he expected that I would be one too," Folkman says. "When I announced that I wanted to be a doctor, he gave me his blessing, but he said, 'You should be a rabbi-like doctor.' 'What's that?' I asked, and he said: 'You should always be of service.' "
* He declared the end of history—and fears the end of human nature
Francis Fukuyama, 50
Dean of Faculty and Professor of International Political Economy, School of Advanced International Studies of Johns Hopkins University
Fukuyama made a splash in 1989 with an essay defining history as an argument over the best system of government. He concluded that, with Communism crumbling, Western liberal democracy would be "the final form of human government." Fukuyama expanded his theory in the 1992 bestseller The End of History and the Last Man. In his latest book, Our Posthuman Future, Fukuyama argues that manipulating DNA could someday prove disastrous: "What will happen to political rights once we are able, in effect, to breed some people with saddles on their backs, and others with boots and spurs?"