http://libertytree.ca/quotes/Benjamin.Franklin.Quote.21EA
Outside Independence Hall when the Constitutional Convention of 1787 ended, Mrs. Powel of Philadelphia asked Benjamin Franklin, "Well, Doctor, what have we got, a republic or a monarchy?" With no hesitation whatsoever, Franklin responded, "A republic, if you can keep it."
-- Benjamin Franklin
(1706-1790) US Founding Father
1787
Source: as recorded by Constitution signer James McHenry in a diary entry.