Guth’s solutions started a revolution in cosmology, but his initial excitement was soon followed by anxiety. He was a young researcher with no faculty appointment, and he was unsure about his theory. “I was very nervous about it because I felt there were too many things about it that I really didn’t understand. I was afraid it was going to somehow blow up.” Despite his concerns, in early 1980 Guth explained inflation in a series of lectures for cosmologists around the country.