It is important to note that Rousseau uses the word “government” to refer
solely to the executive branch, rather than in its contemporary (particularly American) usage as a synonym for “state” as a whole. Similarly, his use of the word “prince” is very unconventional, but essentially it refers to the entire administration. (It may be a reference to Rousseau’s predecessor Niccolò Machiavelli, who is best remembered for the guide to statecraft
The Prince.) The technical difference between “moral” and “physical” causes, which is borrowed from earlier philosophers, allows Rousseau to establish a philosophical justification for the separation of powers between the sovereign (which establishes the will of the people) and the executive or government (which enacts that will).