Perhaps the real root cause of upheaval such as pervasive discontent correlates with occurrences of revolutionary art. Perhaps the art then acts as an amplifie

Perhaps the real root cause of upheaval such as pervasive discontent correlates with occurrences of revolutionary art. Perhaps the art then acts as an amplifier or accelerator of the discontent, creating a feedback loop. Clearly it helps when the "art" is easily distributed and widely understood (printing press, literacy).