A quarrel apparently sparked a stabbing Wednesday afternoon in Old Town that left a 59-year-old man in critical condition, police said. Around 2:40 p.m., the 59-year-old was arguing with someone in the 1400 block of North Sedgwick Street when he was stabbed in the abdomen with a sharp object, Chicago police said. He was taken to Northwestern Memorial Hospital where he was in critical condition, police said. No one was in custody.