Nelson Mandela spent 27 years in jail before becoming president and father of a nation. While "only" 4 years, Muhammad Ali sacrificed what would have been the

Nelson Mandela spent 27 years in jail before becoming president and father of a nation. While "only" 4 years, Muhammad Ali sacrificed what would have been the prime of his boxing career as a conscientious objector. He was famous as a great athlete before, but transcended it after. Alexander Calder was an engineer for about ten years before becoming one of the great artists of the 20th century. Many other examples.