premise: His addle-brained knight-errant , self appointed to the ridiculous position in an <mask> when armor had already been relegated to museums and the chivalrous code of knight-errantry had become a joke , is , as Cervantes no doubt intended , a gaunt but gracious symbol of good , moving soberly and sincerely in a world of cynics , hypocrites and rogues .
hypothesis: the proper context for <mask> here should be an era of history having some distinctive feature