"How easy it would have been flatly to have told the boy that his pilgrim was only an old tramp of some kind, and then to have commanded him not to think otherwise. But by allowing the boy to see that a question was possible, he had rendered such a command ineffective before he uttered it. Insofar as thought could be governed at all, it could only be commanded to follow what reason affirmed anyhow; command it otherwise, and it would not obey."

“Listen, are we helpless? Are we doomed to do it again and again and again? Have we no choice but to play the Phoenix in an unending sequence of rise and fall? Assyria, Babylon, Egypt, Greece, Carthage, Rome, the Empires of Charlemagne and the Turk: Ground to dust and plowed with salt. Spain, France, Britain, America — burned into the oblivion of the centuries. And again and again and again. Are we doomed to it, Lord, chained to the pendulum of our own mad clockwork, helpless to halt its swing? This time, it will swing us clean to oblivion, he thought.”

“Abbot Zerchi smiled thinly. 'You don't have a soul, Doctor. You are a soul. You have a body, temporarily.'”

“The old man was sad as he sat on his porch. He knew so little of the Great Purpose. Why must his seed fling itself starward? He knew that it must — but he lacked a reason. His grandchildren played in the twilight, played space-games, although there was not yet a starship on the planet.”

“Whatever you specialize in, another specialty will either gobble you, or find a way to replace you. If you get what looks like a secure niche, somebody'll come along and wall you up in it and write your epitaph on it. And the more specialized a society gets, the more dangerous it is for the pure specialist. You think an electronic engineer in any safer than an actor? Or a ditch-digger?”

“Objective evidence is the ultimate authority. Recorders may lie, but Nature is incapable of it.”

“When Holy Church occasionally hinted that she still considered her authority to be supreme over all nations and superior to the authority of states, men in these times tended to snicker.”