“And he could not take the chance of putting his certain ignorance against this man's possible knowledge.”

“He did not know, and perhaps this doctor did. And he could not take the chance of pitting his certain ignorance against this man's possible knowledge. He was trapped as his people were always trapped, and would be until, as he had said, they could be sure that the things in the books ere really in the books.”

“He wished to ignore all but here and now, to be as though he had only just entered the world and were destined to be eternal. Bus his memory survived, even though he never deliberately made use of it; and though the things which had been Isabels were destoryed, he could not guard against chance reminders. Chance had found many gaps in his defenses this morning.”

“Is there any knowledge in the world which is so certain that no reasonable man could doubt it?”

“He who is unaware of his ignorance will only be misled by his knowledge.”

“A blind man's world is bounded by the limits of his touch; an ignorant man's world by the limits of his knowledge: a great man's world by the limits of his vision.”