It is useless to distinguish the morality of a nation from the objects of its esteem; both depend on the same principle and are necessarily indistinguishable. There is no people on earth the choice of whose pleasures is not decided by opinion rather than nature.
 Jean-Jacques Rousseau, The Social Contract (1762). copy citation

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

Context

“AS the law is the declaration of the general will, the censorship is the declaration of the public judgment: public opinion is the form of law which the censor administers, and, like the prince, only applies to particular cases.
The censorial tribunal, so far from being the arbiter of the people's opinion, only declares it, and, as soon as the two part company, its decisions are null and void.
It is useless to distinguish the morality of a nation from the objects of its esteem; both depend on the same principle and are necessarily indistinguishable. There is no people on earth the choice of whose pleasures is not decided by opinion rather than nature. Right men's opinions, and their morality will purge itself. Men always love what is good or what they find good; it is in judging what is good that they go wrong. This judgment, therefore, is what must be regulated.” source