"I don’t get no respect," said Rodney Dangerfield, thousands of times. It was one of the great taglines in show-business history. It was the basis of his act—the denial of respect. Whatever his protestations, Rodney was one of the most beloved entertainers of the 1970s, ’80s, and ’90s. There is now a biography, Nothin’ Comes Easy, by Michael Seth Starr. Mr. Starr has written many biographies of entertainers, and several of comedians such as Dangerfield. His other subjects include Joey Bishop, Redd Foxx, and Don Rickles. You may prefer to read a long magazine piece about Dangerfield. You may prefer...