“If we resort for a criterion to the different principles on which different forms of government are established, we may define a republic to be, or at least may bestow that name on, a government which derives all its powers directly or indirectly from the great body of the people, and is administered by persons holding their offices during pleasure, for a limited period, or during good behavior. It is essential to such a government that it be derived from the great body of the society, not from an inconsiderable proportion, or a favored class of it.” What is James Madison expressing in this excerpt (explain in 2-3 sentences)?