Celebrity Series of Boston kicks off the 50th Anniversary of Alvin Ailey American Dance Theater’s first Boston appearance with “REVELATIONS: The Legacies of Alvin Ailey and Boston’s Elma Lewis,” a free, lively, public discussion among arts and dance leaders that looks at the legacy of Alvin Ailey’s work alongside that of Boston arts and social justice pioneer Elma Lewis. Moderated by WGBH news and public affairs personality Callie Crossley, the discussion is headlined by former Ailey dancer and Artistic Director Emerita Judith Jamison, and includes Boston-based panelists E. Barry Gaither, Director and Curator of the Museum of the National Center of Afro-American Artists; Betty Hillmon, director of the Boston City-Wide String Orchestra; Shaumba¬-Yandje Dibinga, Founding Artistic & Executive Director of the Roxbury-based OrigiNation Cultural Arts Center; and Jean Appolon, Artistic Director of Jean Appolon Expressions.