"Ali" author on painting a "real" picture of the legendary boxer
Cassius Clay exploded onto the scene in 1960 as the audacious boxer known as the Louisville Lip. Clay would soon become Muhammad Ali and change the course of American history first as a heavyweight champion and in later years as a civil rights activist, anti-war crusader, and a beloved figure who valiantly fought Parkinson's disease. Jonathan Eig discusses his epic new biography, "Ali: A Life." Anthony Mason reports.