Getting a phone call from an unidentified number in Chicago in late summer is a fantasy many artists, scientists and other creative people have entertained. But that doesn’t mean it seems real when it actually happens.

“I thought I was having a psychotic breakdown,” the playwright Branden Jacobs-Jenkins said of his reaction to learning several weeks ago that he was among the 23 people selected as 2016 fellows of the John D. and Catherine T. MacArthur Foundation.

“I went out on the street, and ran into a friend,” Mr. Jacobs-Jenkins continued. “I had him look at my cellphone, just to confirm that the call had been real.”