At MIT, where Gates made the fourth of five stops on a weeklong college tour Thursday, he recalled the early excitement of the computer revolution when he was a student just up the road at Harvard. He tried to persuade students there are still exciting academic and practical challenges in the field.
"It's not yet the machine that we envisioned in terms of ease of use or the breadth of things to be done," Gates said of the computer. "But we have a good rough draft."
It may seem a curious message to take to MIT, a campus that's as wired as any and is bursting with talented young programmers who will soon be working in the field. But even at MIT, the appeal of studying pure computer science has dwindled recently. The number of computer science majors is down about 30 percent in the last three or four years, said John V. Guttag, head of the school's electrical engineering and computer science departments.
"Some number of years ago, we were the only game in town. If you were interested in computer software, you studied computer science," Guttag said after Gates' speech to about 1,000 students.
Now, however, computers are so integral to other fields like engineering and even biology that much of the expertise is migrating elsewhere. That may not be such a bad thing, Guttag said, but it has diverted attention from the pure software challenges that computer scientists try to tackle.
Those challenges were the subject of Gates' talk Thursday, as well as similar ones this week at the University of Illinois, Carnegie Mellon University and Cornell University. Later Thursday, he was scheduled to address a smaller audience at Harvard, the school he dropped out of in the 1970s to start Microsoft.
Gates outlined a broad range of tasks he sees for the field in the coming years, from radical re-thinking of computer screens to mastering wireless technology to improving business productivity software, security and artificial intelligence.
"These science problems are tough but they're fun to work on," Gates said. "It's not just somebody isolated, doing coding all night, though if you want to do that we still have plenty of jobs like that."
Sunjesh Bagaria, an MIT senior computer science major, said he came to the talk because, "as far as software and technology goes, Bill Gates is the messiah, basically." But he shared Gates' concern that computer science isn't the hot academic field it once was.
"Definitely some of the luster has worn off the last couple of years," said Bagaria, 21. "There's a lot of people running to other industries with computer science degrees. It's good of him to try to stop the brain drain."
Earlier Thursday, Gates met privately with some MIT computer science faculty members, before his presentation to an audience mostly of students. Freshmen, who have yet to pick majors, were given first crack at tickets.
Gates was scheduled to host a similar, smaller event with Harvard students later in the day.
Gates faced questions from students on a range of topics, from Microsoft's $100 billion cash pile to a recent paper by security expert Dan Geer questioning whether a "monoculture" of Microsoft operating systems is a threat to global computing security.
A variety of operating systems, Gates replied to the Geer question, only "increases the threat area" and "doesn't make information any more secure."