One way to combat global warming, Turner said, is to stabilize the population.

"We're too many people; that's why we have global warming," he said. "Too many people are using too much stuff."

Turner suggested that "on a voluntary basis, everybody in the world's got to pledge to themselves that one or two children is it."

Admitting that he's "always suffered from foot-in-the-mouth disease," Turner added, "I've gotten a lot better, though. It's been a long time since anybody caught me saying something stupid."