The quote is interesting. Is Rousseau assuming there was a "European" identity, or may he simply be referring to the various peoples who occupied "continental" Europe?
Certainly cosmopolitanism was not spread simply by the advance of Enlightenment ideas. I have been arguing for a long time that the spread of "Enlightenment" was as much due to commerce as to the power of ideas simply sweeping aside superannuated notions and prejudices. "Europeanism," however, also had a material component, the spread of similar goods and services across a region uniting people in habits on consumption and manners. It is become conventional wisdom that trade and commerce and the long-range communications that result are evil. Thus, Rousseau, who linked commerce to the decay of manners. I don't know, however, if he specifically linked it with cosmopolitanism. Here is another Frenchman, François-Noel Babeuf (1760-1797), discoursing on greed, who must be considered a utopian:
"Society must be made to operate in such a way that it eradicates once and for all the desire of a man to become richer, or wiser, or more powerful than others."
Similarly, Morelly in Code de la Nature, of 1755:
"The only vice that I perceive in the universe is Avarice; all the others, by whatever name they be known, are only variations, degrees, of this one."
I don't believe Goethe ever discoursed in this way, though I am willing to be corrected.
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