Because citizens do not govern the state themselves but through representatives, republics may be distinguished from direct democracy, though modern representative democracies are by and large republics. The term
republic may also be applied to any form of government in which the head of state is not a hereditary monarch.
Prior to the 17th century, the term was used to designate any state, with the exception of tyrannical regimes. Derived from the Latin expression
res publica (“the public thing”),
the category of republic could encompass not only democratic states but also oligarchies, aristocracies, and monarchies. In
Six Books of the Commonwealth (1576), his canonical study of sovereignty, the French political philosopher Jean Bodin thus offered a far-reaching definition of the republic: “the rightly ordered government of a number of families, and of those things which are their common concern, by a sovereign power.” Tyrannies were excluded from this definition, because their object is not the common good but the private benefit of a single individual.