For years, Gac Filipaj mopped floors, cleaned toilets and took out trash at Columbia University . A refugee from war-torn Yugoslavia, he eked out a living working for the Ivy League school. But Sunday was payback time: The 52-year-old janitor donned a cap and gown to graduate with a bachelor's degree in classics. As a Columbia employee, he didn't have to pay for the classes he took. His favorite subject was the Roman philosopher and statesman Seneca, the janitor said during a break from his work at Lerner Hall , the student union building he cleans. "I love Seneca's letters because they're written in the spirit in which I was educated in my family — not to look for fame and fortune, but to have a simple, honest, honorable life," he said. His graduation with honors capped a dozen years of studies, including readings in ancient Latin and Greek. "This is a man with great pride, whether he's doing custodial work or academics," said Pe...