The Machine is only a tool after all, which can help humanity progress faster by taking some of the burdens of calculations and interpretations off i… - Isaac Asimov

Why do you think it is stupid to go to windows instead of to doors?"

"Because you advertise what you're trying to hide, silly. If I have a secret, I don't put tape over my mouth and let everyone know I have a secret. I talk just as much as usual, only about something else. Didn't you ever read any of the sayings of Salvor Hardin? He was our first Mayor, you know."

"Yes, I know."

"Well, he used to say that only a lie that wasn't ashamed of itself could possibly succeed. He also said that nothing had to be true, but everything had to sound true. Well, when you come in through a window, it's a lie that's ashamed of itself and it doesn't sound true."

"Then what would you have done?"

"If I had wanted to see my father on top secret business, I would have made his acquaintance openly and seen him about all sorts of strictly legitimate things. And then when everyone knew all about you and connected you with my father as a matter of course, you could be as top secret as you wanted and nobody would ever think of questioning it.

How could any number of people — all together — know enough? It reminded Seldon of a puzzle that had been presented to him when he was young: Can you have a relatively small piece of platinum, with handholds affixed, that could not be lifted by the bare, unaided strength of any number of people, no matter how many? The answer was yes. A cubic meter of platinum weighs 22,420 kilograms under standard gravitational pull. If it is assumed that each person could heave 120 kilograms up from the ground, then 188 people would suffice to lift the platinum. — But you could not squeeze 188 people around the cubic meter so that each one could get a grip on it. You could perhaps not squeeze more than 9 people around it. And levers or other such devices were not allowed. It had to be "bare, unaided strength." In the same way, it could be that there was no way of getting enough people to handle the total amount of knowledge required for psychohistory, even if the facts were stored in computers rather than in individual human brains. Only so many people could gather round the knowledge, so to speak, and communicate it.

If, from a distance of seven thousand parsecs, the fall of Kalgan to the armies of the Mule had produced reverberations that had excited the curiosity of an old Trader, the apprehension of a dogged captain, and the annoyance of a meticulous mayor – to those on Kalgan itself, it produced nothing and excited no one. It is the invariable lesson to humanity that distance in time, and in space as well, lends focus. It is not recorded, incidentally, that the lesson has ever been permanently learned.