When he was asked, toward the end of lunch, where he thought computing might be headed, he paused to rephrase the question. “I’ll tell you what I’d like to see happen,” he said, and began discussing what the future was supposed to have looked like, back in his 1960s childhood. He ticked off the tropes of what he called “techno-optimistic science fiction,” including flying cars and jetpacks. And then computers went from being things that filled a room to things that could fit on a desk, and the economy and industries changed. “The kinds of super-bright, hardworking geeky people who, 50 years ago, would have been building moon rockets or hydrogen bombs or what have you have ended up working in the computer industry, doing jobs that in many cases seem kind of ignominious by comparison.”

Again, a beat. A consideration, perhaps, that he is talking about the core readership for his best sellers. No matter. He’s rolling. He presses on.

“What I’m kind of hoping is that this is just kind of a pause, while we assimilate this gigantic new thing, ubiquitous computing and the Internet. And that at some point we’ll turn around and say, ‘Well, that was interesting — we have a whole set of new tools and capabilities that we didn’t have before the whole computer/Internet thing came along.’ ”

He said people should say, “Now let’s get back to work doing interesting and useful things.”

The needs of the world are great: New forms of energy, space transportation and infrastructure all need to be tackled with imagination and innovation, he said. He grew animated as he discussed his latest initiative: He is now pushing for a return to a can-do American culture that can “get big stuff done.”