Both Nietzsche and Rousseau, in their own ways, created symbolic orders – specialized languages – that put “something” in the “empty space” left when we stopped living in a world of constrained complexity.
Both Nietzsche and Rousseau, themselves, were keys to their symbolic orders. Others (unwittingly, because this is what we do) mimicked their desires. Some mimicked in rivalry and some in admiration.
Their (adopted) desires set the stage for their competition to be the suffering servants of art or social science.