Among the most formidable of the obstacles which the new Constitution will have to encounter may readily be distinguished the obvious interest of a certain class of men in every State to resist all changes which may hazard a diminution of the power, emolument, and consequence of the offices they hold under the State establishments.

Hamilton, Alexander. "No. 15: Its great defect: can only legislate for states.--Hamilton." The Federalist: A Commentary on the Constitution of the United States, edited by Robert Scigliano. The Modern Library, 2001.

Jefferson, Thomas. The Writings of Thomas Jefferson: Being His Autobiography, Correspondence, Reports, Messages, Addresses, and Other Writings, Official and Private, edited by H. A. Washington. Vol. 9, Cambridge University Press, 2011.

Socrates. Quoted in Republic, written by Plato, translated by Desmond Lee. Penguin Classics, 2007.