There are still two forms besides democracy and oligarchy; one of them is universally recognized and included among the four principal forms of government, which are said to be (1) monarchy, (2) oligarchy, (3) democracy, and (4) the so-called aristocracy or government of the best. But there is also a fifth, which retains the generic name of polity or constitutional government.
AristotleOnce more: there are three offices according to whose directions the highest magistrates are chosen in certain states - guardians of the law, probuli, councilors - of these, the guardians of the law are an aristocratical, the probuli an oligarchical, the council a democratical institution.
AristotleThese two rational faculties may be designated the Scientific Faculty and the Calculative Faculty respectively; since calculation is the same as deliberation, and deliberation is never exercised about things that are invariable, so that the Calculative Faculty is a separate part of the rational half of the soul.
Aristotle