John Addington Symonds,
Renaissance in Italy, Volumes 6 and 7…
“ Thus Guercino owed far less to academical studies than to his own genius. Being Lodovico Caracci's junior by thirty-five years, and Annibale's by thirty, he had ample opportunities for studying the products of their school in Bologna, without joining the Academy. A generation lay between him and the first Eclectics. Nearly the same space of time separated Guercino from the founder of the Naturalists, and it was universally admitted in his lifetime that he owed to Caravaggio in coloring no less than he derived from the Caracci in sobriety and dignity of conception. ”
