The only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others. His own good, either physical or moral, is not a sufficient warrant.

Thoreau, Henry David. "Where I Lived, And What I Lived For." Walden and Civil Disobedience. Signet, 2012.

Madison, James. "No. 51: How to maintain: make the parts check each other. Also, a federal system divides power further.--Madison (or Hamilton)." The Federalist: A Commentary on the Constitution of the United States, edited by Robert Scigliano. The Modern Library, 2001.

Lincoln, Abraham. "Speech at Cincinnati, Ohio, September 17, 1859." Abraham Lincoln: Speeches and Writings 1859-1865, edited by Don E. Fehrenbacher. Library of America, 1989.