A comic writer and performer, he was known for his boundary-pushing routines about racism and social justice and for his work with Richard Pryor and Dave Chappelle.Paul Mooney, the boundary-pushing comedian and comedy writer who made his views on race, racism and social justice abundantly clear as Richard Pryor’s longtime behind-the-scenes partner, a contributor to “In Living Color” and a performer and writer on “Chappelle’s Show,” died on Wednesday at his home in Oakland, Calif. He was 79.The cause was a heart attack, said Cassandra Williams, his publicist. Mr. Mooney was found to have prostate cancer in 2014.If you knew Mr. Pryor’s work, you probably knew Mr. Mooney’s words. The two worked together on the short-lived 1977 variety series “The Richard Pryor Show”; “Pryor’s Place” (1984), Mr. Pryor’s unlikely attempt at a children’s show; television specials; the album and film “Richard Pryor: Live on the Sunset Strip” (1982); the autobiographical film “Jo Jo Dancer, Your Life Is Calling” (1986), which Mr. Pryor starred in and directed; and Mr. Pryor’s 1975 appearance as host on “Saturday Night Live.” That episode included a now-famous escalating-racial-insults job-interview sketch with Chevy Chase, written by Mr. Mooney.In an interview with The New York Times after Mr. Pryor’s death in 2005 at 65, Mr. Mooney described himself as Mr. Pryor’s “Black writer.”As a writer on “In Living Color,” Keenen Ivory Wayans’s hit sketch comedy show that had its premiere on Fox in 1990 with a predominantly Black cast, Mr. Mooney was the inspiration for and co-creator of Homey D. Clown, a less than jovial circus-costumed character who was forced to interact with children (part of his parole agreement) and usually ended up frightening them.As a writer and performer on “Chappelle’s Show” in the early 2000s, Mr. Mooney played Negrodamus, a turbaned mystic who foretold the future (Hillary Rodham Clinton’s political prospects, Arnold Schwarzenegger and Maria Shriver’s marriage), appeared as the expert in “Ask a Black Dude” and reviewed movies alongside white female critics. Discussing “Gone With the Wind,” he revealed that Hattie McDaniel, who played the enslaved character known as Mammy, had been reincarnated as Oprah Winfrey — for the money.Mr. Mooney’s film roles included the singer Sam Cooke in “The Buddy Holly Story” (1978) and Junebug, an old-school stand-up comedian with equal amounts of dignity, integrity and genius, in “Bamboozled” (2000), Spike Lee’s dark farce about a television network bringing back the minstrel-show genre.On “Chappelle’s Show” in the early 2000s, Mr. Mooney played Negrodamus, a turbaned mystic who foretold the future.Comedy CentralPaul Mooney was born Paul Gladney on Aug. 4, 1941, in Shreveport, La., to George Gladney and LaVoya Ealy, who were both teenagers. When Paul was 7, he moved with his mother and her parents to Oakland, where he was largely raised by his grandmother, Aimay Ealy.Although some reports said he had taken his stage surname from the Hollywood actor Paul Muni, he corrected that in his 2007 memoir, “White Is the New Black.” His family loved nicknames, he wrote, and his grandmother just started calling him Mooney when he was a child.Paul was 14 when he and his mother moved to nearby Berkeley. There, at a local movie theater, he won his first “hambone” contest, performing an African-American stomping dance that involves slapping and patting the body like a drum. It was then that he realized that he loved applause — and prize money.He had his first taste of fame when he became a teenage regular on a local dance-party television show. After the Army (he was drafted and served in Germany), he came home to all kinds of sales jobs and, even more, to a future in entertainment. He did his first stand-up comedy (alongside friends who were folk singers), created a Black improvisational group called the Yankee Doodle Bedbugs, and joined the noted improv group the Second City. He also took a job for a while as ringmaster of the traveling Gatti-Charles Circus, which, he said, just called for looking good and telling jokes.Mr. Mooney and Richard Pryor (seated) attended the premiere of Spike Lee’s concert film “The Original Kings of Comedy” in Los Angeles in 2000. With them were, from left, Walter Latham, one of the film’s producers, along with Cedric the Entertainer, Steve Harvey, Mr. Lee and D.L. Hughley.Fred Prouser/ReutersHe met Mr. Pryor in the late 1960s at a party, and they soon discovered that their personal lives were antithetical. “Pryor was a self-loathing, drug-addicted genius, Mooney an industrious teetotaler, but they bonded over laughs and a distrust of the white Hollywood power structure,” The Los Angeles Times wrote in 2010.Mr. Mooney continued his comedy career after Mr. Pryor’s death, preserving his routines in documentaries and DVDs like “The Godfather of Comedy” (2012) and “Jesus Is Black — So Was Cleopatra — Know Your History” (2007).In “Jesus Is Black,” his three sons — Shane (whose mother was Yvonne Carothers, whom Mr. Pryor married in 1973) and Daryl and Dwayne (twin sons from an earlier relationship) — appeared as themselves. Complete information on survivors was not immediately available.Mr. Mooney had strong opinions, even about himself.“Whatever that thing is that white people like in Blacks, I don’t have it,” he wrote in his memoir. “Maybe it’s my arrogance or my self-assurance or the way I carry myself, but whatever it is, I don’t have it.”Marie Fazio contributed reporting. More