Inferno 16.118–120
Dante, as Virgil signals into the abyss
Ahi quanto cauti li uomini esser dienno
presso a color che non veggion pur l’ovra,
ma per entro i pensier miran col senno!
Ah, how cautious men ought to be
near those who see not only the act,
but with wisdom gaze inside our thoughts!