Federalist No. 9, by Alexander Hamilton (The Union as a Safeguard Against Domestic Faction and Insurrection)

“But it is not to be denied that the portraits they have sketched of republican government were too just copies of the originals from which they were taken. If it had been found impracticable to have devised models of a more perfect structure, the enlightened friends to liberty would have been obliged to abandon the cause of that species of government as indefensible. The science of politics, however, like most other sciences, has received great improvement. The efficacy of various principles is now well understood, which were either not known at all, or imperfectly known to the ancients. The regular distribution of power into distinct departments; the introduction of legislative balances and checks; the institution of courts composed of judges holding their offices during good behavior; the representation of the people in the legislature by deputies of their own election: these are wholly new discoveries, or have made their principal progress towards perfection in modern times. They are means, and powerful means, by which the excellences of republican government may be retained and its imperfections lessened or avoided. To this catalogue of circumstances that tend to the amelioration of popular systems of civil government, I shall venture, however novel it may appear to some, to add one more, on a principle which has been made the foundation of an objection to the new Constitution; I mean the ENLARGEMENT of the ORBIT within which such systems are to revolve, either in respect to the dimensions of a single State or to the consolidation of several smaller States into one great Confederacy. The latter is that which immediately concerns the object under consideration. It will, however, be of use to examine the principle in its application to a single State, which shall be attended to in another place”.