The term 'Common Sense Author' refers to Thomas Paine, an English-American political activist, philosopher, and revolutionary. He is best known for his 1776 pamphlet 'Common Sense', which argued for American independence from Great Britain. Paine was a major influence on the American Revolution and wrote many influential works, including 'The Rights of Man' and 'The Age of Reason'. His last name is Paine, which is five letters long. His full name is Thomas Paine, which is eleven letters long.