Who was Duerer? He has told us himself very simply, and more fully than men of his type generally do; for he was not, like Montaigne, one whose chief study was himself. Yet, though he has done this, it is not easy for us to fully understand him. It is perhaps impossible to place oneself in the centre of that horizon which was of necessity his and belonged to his day, a vast circle from which men could no more escape than we from ours; this cage of iron ignorance in which every human soul is trapped, and to widen and enlarge which every heroic soul lives and dies.