The larger groups; the billions that occupied planets; the trillions that occupied Sectors; the quadrillions that occupied the whole Galaxy, became, not simply human beings, but gigantic forces amenable to statistical treatment - so that to Hari Seldon, the future became clear and inevitable, and the Plan could be set up.

The same basic developments of mental science that had brought about the development of the Seldon Plan, thus made it also unnecessary for the First Speaker to use words in addressing the Student.

Every reaction to a stimulus, however slight, was completely indicative of all the trifling changes, of all the flickering currents that went on in another's mind. The First Speaker could not sense the emotional content of the Student's instinctively, as the Mule would have been able to do - since the Mule was a mutant with powers not ever likely to become completely comprehensible to any ordinary man, even a Second Foundationer - rather he deduced them, as the result of intensive training.

Since, however, it is inherently impossible in a society based on speech to indicate truly the method of communication of Second Foundationers among themselves, the whole matter will be hereafter ignored. The First Speaker will be represented as speaking in ordinary fashion, and if the translation is not always entirely valid, it is at least the best that can be done under the circumstances.

It will be pretended therefore, that the First Speaker did actually say, "First, I must tell you why you are here," instead of smiling just so and lifting a finger exactly thus.

The First Speaker said, "You have studied mental science hard and well for most of your life. You have absorbed all your teachers could give you. It is time for you and a few others like yourself to begin your apprenticeship for Speakerhood."

Agitation from the other side of the desk.

"No - now you must take this phlegmatically. You had hoped you would qualify. You had feared you would not. Actually, both hope and fear are weaknesses. You knew you would qualify and you hesitate to admit the fact because such knowledge might stamp you as cocksure and therefore unfit. Nonsense! The most hopelessly stupid man is he who is not aware that he is wise. It is part of your qualification that you knew you would qualify."

Relaxation on the other side of the desk.

"Exactly. Now you feel better and your guard is down. You are fitter to concentrate and fitter to understand. Remember, to be truly effective, it is not necessary to hold the mind under a tight, controlling barrier which to the intelligent probe is as informative as a naked mentality. Rather, one should cultivate an innocence, an awareness of self, and an unself-consciousness of self which leaves one nothing to hide. My mind is open to you. Let this be so for both of us."

He went on. "It is not an easy thing to be a Speaker. It is not an easy thing to be a Psychohistorian in the first place; and not even the best Psychohistorian need necessarily qualify to be a Speaker. There is a distinction here. A Speaker must not only be aware of the mathematical intricacies of the Seldon Plan; he must have a sympathy for it and for its ends. He must love the Plan; to him it must be life and breath. More than that it must even be as a living friend.

"Do you know what this is?"

The First Speaker's hand hovered gently over the black, shining cube in the middle of the desk. It was featureless.

"No, Speaker, I do not."

"You have heard of the Prime Radiant?"

"This?" - Astonishment.

"You expected something more noble and awe-inspiring? Well, that is natural. It was created in the days of the Empire, by men of Seldon's time. For nearly four hundred years, it has served our needs perfectly, without requiring repairs or adjustment. And fortunately so, since none of the Second Foundation is qualified to handle it in any technical fashion." He smiled gently. "Those of the First Foundation might be able to duplicate this, but they must never know, of course."

He depressed a lever on his side of the desk and the room was in darkness. But only for a moment, since with a gradually livening flush, the two long walls of the room glowed to life. First, a pearly white, unrelieved, then a trace of faint darkness here and there, and finally, the fine neatly printed equations in black, with an occasional red hairline that wavered through the darker forest like a staggering rillet.

"Come, my boy, step here before the wall. You will not cast a shadow. This light does not radiate from the Radiant in an ordinary manner. To tell you the truth, I do not know even faintly by what medium this effect is produced, but you will not cast a shadow. I know that."

They stood together in the light. Each wall was thirty feet long, and ten high. The writing was small and covered every inch.

"This is not the whole Plan," said the First Speaker. "To get it all upon both walls, the individual equations would have to be reduced to microscopic size - but that is not necessary. What you now see represents the main portions of the Plan till now. You have learned about this, have you not?"

"Yes, Speaker, I have."

"Do you recognize any portion."

A slow silence. The student pointed a finger and as he did so, the line of equations marched down the wall, until the single series of functions he had thought of - one could scarcely consider the quick, generalized gesture of the finger to have been sufficiently precise - was at eye-level.

The First Speaker laughed softly, "You will find the Prime Radiant to be attuned to your mind. You may expect more surprises from the little gadget. What were you about to say about the equation you have chosen?"

"It," faltered the Student, "is a Rigellian integral, using a planetary distribution of a bias indicating the presence of two chief economic classes on the planet, or maybe a Sector, plus an unstable emotional pattern."

"And what does it signify?"

"It represents the limit of tension, since we have here" - he pointed, and again the equations veered - "a converging series."

"Good," said the First Speaker. "And tell me, what do you think of all this. A finished work of art, is it not?"

"Definitely!"

"Wrong! It is not." This, with sharpness. "It is the first lesson you must unlearn. The Seldon Plan is neither complete nor correct. Instead, it is merely the best that could be done at the time. Over a dozen generations of men have pored over these equations, worked at them, taken them apart to the last decimal place, and put them together again. They've done more than that. They've watched nearly four hundred years pass and against the predictions and equations, they've checked reality, and they have learned.

"They have learned more than Seldon ever knew, and if with the accumulated knowledge of the centuries we could repeat Seldon's work, we could do a better job. Is that perfectly clear to you?"

The Student appeared a little shocked.

"Before you obtain your Speakerhood," continued the First Speaker, "you yourself will have to make an original contribution to the Plan. It is not such great blasphemy. Every red mark you see on the wall is the contribution of a man among us who lived since Seldon. Why… why-" He looked upward, "There!"

The whole wall seemed to whirl down upon him.

"This," he said, "is mine." A fine red line encircled two forking arrows and included six square feet of deductions along each path. Between the two were a series of equations in red.