The difference of Common-wealths, consisteth in the difference of the Soveraign, or the Person representative of all and every one of the Multitude. And because the Soveraignty is either in one Man, or in an Assembly of more than one; and into that Assembly either Every man hath right to enter, or not every one, but Certain men distinguished from the rest; it is manifest, there can be but Three kinds of Common-wealth. For the Representative must needs be One man, or More: and if more, then it is the Assembly of All, or but of a Part. When the Representative is One man, then is the Common-wealth a MONARCHY: when an Assembly of All that will come together, then it is a DEMOCRACY, or Popular Common-wealth: when an Assembly of a Part onely, then it is called an ARISTOCRACY. Other kind of Common-wealth there can be none: for either One, or More, or All, must have the Soveraign Power (which I have shewn to be indivisible) entire.
There be other names of Government, in the Histories, and books of Policy; as Tyranny, and Oligarchy: But they are not the names of other Formes of Government, but of the same Formes misliked. For they that are discontented under Monarchy, call it Tyranny; and they that are displeased with Aristocracy, called it Oligarchy: So also, they which find themselves grieved under a Democracy, call it Anarchy, (which signifies want of Government;) and yet I think no man believes, that want of Government, is any new kind of Government: nor by the same reason ought they to believe, that the Government is of one kind, when they like it, and another, when they mislike it, or are oppressed by the Governours.
(Thomas Hobbes, Leviathan, rev. student ed., ed. Richard Tuck, Cambridge Texts in the History of Political Thought, ed. Raymond Geuss and Quentin Skinner [Cambridge: Cambridge University Press, 1996], chap. 19, pp. 129-30 [italics in original] [first published in 1651])
Note from KBJ: Aristotle (384-322 BC), in Book III, Chapter 7 of The Politics, made a similar typology of constitutions, or civic bodies. Instead of distinguishing between "liked" and "misliked" kinds of commonwealth, as Hobbes did, he distinguished between "right constitutions" (in which those who rule do so "with a view to the common interest") and "perversions" (in which those who rule do so with a view to "personal interest"). Right rule by one is kingship (Hobbes's monarchy); right rule by a few is aristocracy (same in Hobbes); right rule by many is constitutional government (Hobbes's democracy). Perverted rule by one is tyranny (same in Hobbes); perverted rule by a few is oligarchy (same in Hobbes); perverted rule by many is democracy (Hobbes's anarchy). Note the different connotations of the word "democracy" in these typologies. Aristotle used the term to describe a perverted form of government. Hobbes used it to describe a "liked" form of government.
Note 2 from KBJ: Here is Aristotle:
Tyranny is a government by a single person directed to the interest of that person; Oligarchy is directed to the interest of the well-to-do; Democracy is directed to the interest of the poor. None of these benefits the common interest.
Interestingly, progressives think of the United States government (especially under George W. Bush) as an oligarchy, while conservatives think of it (especially under Barack Obama) as a democracy. Both think that our government is perverted. They disagree as to how it is perverted.