Shelley comments in the main text of A Defence that many of those thinkers whom he most admires for their writings in the cause of the liberation of humanity—John Locke, David Hume, Edward Gibbon, Voltaire, Rousseau, and their followers—made almost no real impact on the world. Of these, he only really has time for Rousseau, and he gives an interesting explanation for this in a footnote: only Rousseau was a poet,
