To be legitimate, the government must be, not one with the Sovereign, but its minister. In such a case even a monarchy is a Republic.
 Jean-Jacques Rousseau, The Social Contract (1762). copy citation

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Author Jean-Jacques Rousseau
Source The Social Contract
Topic government monarchy
Date 1762
Language English
Reference Of the Social Contract, or Principles of Political Law, Book II
Note Translated by George Douglas Howard Cole
Weblink https://en.wikisource.org/wiki/The_Social_Contract/Book_II

Context

“The terminology made it unavoidable, considering the poverty of the language; but wait and see.
10. I understand by this word, not merely an aristocracy or a democracy, but generally any government directed by the general will, which is the law. To be legitimate, the government must be, not one with the Sovereign, but its minister. In such a case even a monarchy is a Republic. This will be made clearer in the following book.
11. A people becomes famous only when its legislation begins to decline. We do not know for how many centuries the system of Lycurgus made the Spartans happy before the rest of Greece took any notice of it.
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