SAO PAULO, BRAZIL.- The 25th Sao Paulo Biennial has opened, and curator Alfons Hug has commented, "Sao Paulo has always been the only biennial among the 50 that exist worldwide to have a historic nucleus," he told the Associated Press. "To eliminate it is not revolutionary, it's very obvious." It's also controversial, as the country's most influential newsweekly called it "a biennial without content" -- a comment not that different than those spoken at the "2002 Biennial Exhibition" at the Whitney Museum. The Sao Paulo show, the largest in the southern hemisphere, is on view until June 2, 2002, with 190 artists from 70 countries taking up the theme of "Metropolitan Iconographies” at the 30,000-square-meter exhibition space on three floors of the Ciccillo Matarazzo Pavilion.