Dan Schulman, the chief executive of Verizon, said this week that some form of artificial general intelligence is likely to arrive within six to 18 months, one of the most aggressive forecasts yet from the head of a large American company.

Mr. Schulman made the prediction in conversation with Fortune’s Diane Brady at the Ford Pro Accelerate event in Detroit. “The models that we see today are the worst models we’ll ever use in our lives,” he said. “Every two months, there’s a step function change in the power of the models. I think we get to some form of A.G.I. in the next six to 18 months. I think it’s right on us.”

Two years beyond that, he said, comes “the era of quantum,” which he called “everything today times 1,000,” and by 2030 or 2035, “a pretty good form of humanoid robotics.” His summary: “We’ve got a decade of intense change ahead of us.”

“I think you’ll see the collapse of the 21st century in the next five to 10 years,” Mr. Schulman said. Pressed by Ms. Brady on the word “collapse,” he said he meant speed: “Progress we would have made over 100 years will happen over the next five to 10 years.” Not everyone shares the optimism about what that pace delivers for investors; the hedge fund manager Michael Burry has been accelerating a bet that the A.I. boom breaks by 2027.

Mr. Schulman said the change would reach his own company. Verizon has more than 250,000 employees and contractors and will have to move from “very defined roles and functions” to a “much more fluid organization,” he said. “The technology is coming. There will be safeguards around it. There need to be additional safeguards, but it will continue on.”

Verizon last week announced a $70 million initiative offering free A.I. training to American workers, including people outside the company, working with local organizations on career development. “Our responsibility is to think about what might go wrong; what might we need to address; what might the disruption look like; and how do we put guardrails, training, programs in place to minimize that risk,” Mr. Schulman said. “Everybody’s job is going to shift. I don’t think everybody will land just magically in a better place per se.”

The other executives on the panel described tighter limits on what A.I. can do. Patti Poppe, the chief executive of PG&E, said she had watched a lineman lowered by rope from a helicopter onto a transmission tower in the California mountains. A digitized grid of sensors and predictive software will still need that man, she said: “The same guys who hang on the end of the rope are going to have to get smarter about those kinds of technologies. Somebody’s still going to have to connect that wire to the pole.”

Dave Regnery, the chief executive of Trane Technologies, told students to look up 40-year-old articles about the arrival of personal computers. “They’re identical,” he said of the anxiety. Trane is using A.I. to run buildings’ heating and cooling around actual use, he said; buildings account for 30 percent of all energy and waste 30 percent of that, and his company can run them roughly 15 percent more efficiently than their design baseline, creating demand for technicians rather than simply cutting staff.

Chris Nelson, the chief executive of Stanley Black & Decker, described autonomous robots that read digital construction plans and drill holes for data-center racks on their own, freeing electricians to pull wire and terminate connections. “What do the electricians and other skilled tradespeople not like to do all day? Sit and core drill,” he said, calling A.I. “a companion on the construction site.”

For Dan Peyovich, the chief executive of Dycom, which builds fiber and telecommunications networks with roughly 21,000 employees, the problem is not workers displaced by A.I. but finding enough people to build what the boom requires. “There’s so much infrastructure that has to get put in place for all of this to happen,” he said. Dycom has added paid time off, health coverage and a training facility near Atlanta. “We want to try and create a path for people,” Mr. Peyovich said. “While they’re getting a paycheck, they can learn and find their way.”

Mr. Schulman did not quarrel with the more incremental views around him. His point was that leaders should not bet on a painless adjustment. “We need to be prepared in case a different scenario emerges,” he said, “so that we can make sure that we have skilled workers, whether they be craftsmen or professionals.”