Contributors

Preparing a special issue of TIME like the one you're holding takes careful planning. The biggest problem, says PHILIP ELMER-DEWITT, the assistant managing editor who supervised the project, is the issue's sheer size. "I realized straight off that if I had to edit 92 pages all at once, I'd burst," he says. So he, deputy chief of reporters ANDREA DORFMAN, and TIME's science staff began working on it nearly a year ago; by last fall their list of the greatest minds of the century had been boiled down to a few dozen names. In November Elmer-DeWitt began handing out writing assignments.

Deciding who got those assignments took some creative thought. Elmer-DeWitt was determined to find writers who brought a special expertise to their subject and could also produce graceful prose. NEIL POSTMAN for example, who wrote on TV pioneer Philo Farnsworth, is the author of Amusing Ourselves to Death, an acclaimed study of the impact of television on society. RICHARD RHODES, who profiled nuclear physicist Enrico Fermi, wrote a Pulitzer-prizewinning tome on the making of the atom bomb. Paleoanthropologist DONALD JOHANSON, who discovered the fossil called Lucy, had a long and bumpy relationship with the Leakey family and used this occasion to break a silence with Richard Leakey that lasted nearly two decades.

Some of the choices were more unconventional. At TIME's 75th-anniversary party last year, BILL GATES said his career was particularly influenced by the Wright brothers--so he was chosen to write about them. And though TIME senior writer PAUL GRAY is no computer expert, he was picked to tell the tragic tale of Alan Turing. Says Elmer-DeWitt: "I needed someone who could break the readers' hearts."

Despite all the advance planning, we had to be ready to rethink the issue at any time. A few weeks ago, science-fiction writer BRUCE STERLING persuaded us that the century has been shaped as much by bad scientists as by good ones. We decided on the spot to pull together the feature on "cranks, villains and unsung heroes" that you'll find inside.

Finding just the right art for the issue was its own adventure. Deputy art director MARTI GOLON was looking for someone to paint Swiss child psychologist Jean Piaget, for example, when she chanced on a portrait in an illustration annual. She knew the artist, ETIENNE DELESSERT, as a children's book illustrator and thought, "Wow, this is a perfect solution." She had no idea how perfect. Delessert not only knew Piaget but had worked with him. Delessert sent along a photo of the two collaborating on a book, which we couldn't resist reproducing here. You will find other remarkable, often rare photos inside, thanks to picture editor JAY COLTON and assistant JESSICA TARASKI, along with visual treats of all kinds--charts, graphics and even what looks like a subway map. Use it to guide your own journey through the century. We hope you'll enjoy it as much as we did.