ON WARHOL James Welling, whose one-person exhibitions have appeared at various museums throughout the world, lectures on the work of Andy Warhol. The discussion is part of the Artists on Artists lecture series. Tonight, 6:30 p.m., Dia Art Foundation, 548 W. 22nd St., between Tenth and Eleventh avenues, 212-989-5566, $6 general, $3 seniors, students, and members.

PAPP’S PUBLIC The author of “Joe Papp: An American Life” (Little, Brown), Helen Epstein, discusses the ideas that shaped Papp’s vision for the Public Theater. A book signing and question-and-answer session follow the talk. Tonight, 7 p.m., the Public Theater, 425 Lafayette St. at Astor Place, 212-260-2400, free, reservations recommended.

WAR ON SCREEN New York University’s Center on Law and Security presents a discussion on “Al Qaeda Now: The Media and the War on Terror.” Panelists include a terrorism analyst for CNN, Peter Bergen, and the London bureau chief for Al-Jazeera, Yosri Fouda. An NYU law professor, Stephen Holmes, moderates. Wednesday, 6-8 p.m., New York University, Vanderbilt Hall, Greenberg Lounge, 40 Washington Square South at Macdougal Street, 212-992-8854, free.

HELLO, COLUMBUS Writers Judith Thurman and Ed Rothstein join the editor of “Philip Roth: The Library of America Edition,” Ross Miller, in discussing Mr. Roth’s work and influence. The program is part of the Great New York Writers in Great New York Places series, co-sponsored by the Library of America, the Merchants House Museum, and the City of New York Parks and Recreation Department. Wednesday, 7 p.m., Museum of Jewish Heritage, 36 Battery Place in Battery Park City, 646-437-4202, $15 general, $12 seniors, $10 members and students.

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