Psionic transmissions normally are subject to the inverse square law, but can be received at something beyond normal hearing distance when transmitted forcefully or in a psychically quiet environment. With training, the potentially psi-receptive mind reflexively develops selective damping, providing a large degree of protection against "psi noise." Damping can be cut selectively for screening transmissions, as for seeking one particular mind in a crowd. And when that mind is found, the attention can be focused on it while reception of others remains damped.
Damping is not very effective against transmissions directed specifically toward the receiver, however.
Unexplainable exceptions occur to the inverse square limitation. Occasional transmissions carry thousands of kilometers without apparent weakening. These are highly specific to a receiver or receivers, and the receiver need not be a trained psi. Little is known about this phenomenon and such transmissions cannot be made at will. They are, therefore, of little importance.
There is also a technological exception to the inverse square restriction. Before the Great Death, an instrument called a psi tuner was invented, permitting the narrow focusing of telepathic transmissions to another psi tuner. They are useful only to trained psis.
Precognition and premonition are the other known facets of psi. In the untrained psi these commonly are in the form of symbolic visions, but among trained psis they are usually explicit previews having the same quality and much of the impact of a sensory perception. Premonitions are not necessarily fulfilled, falling into the category of "what will happen if nothing intercedes." Precognition, on the other hand, seems to fall into the category of "what will happen regardless." Many trained psis state they can distinguish them. A strong philosophical case has been made, however, for the contention that there is no precognition in that strict sense, the difference between the experiences lying in the degree of probability that they will be fulfilled.
Premonition and precognition cannot be experienced at will. They occur rarely or possibly never at all to some psis, infrequently to most, and somewhat frequently to a few. Commonly occurring without context, the receiver often cannot understand what he "saw," and the event foreseen may be important or irrelevant to him.
Raadgiver also described the loose organization of psis that had grown up in Europe.
"In the year 2105 there were five billion people on Earth," he said. "Can you imagine that, Nils? That is a thousand taken a thousand times. And then that thousand thousand taken a thousand times again, and five times all of those. It is beyond comprehension. Single towns had more people than probably exist in all the world today. That is our tradition in the Psi Alliance. And then the Great Death came, and within a few weeks so many had died that a man could walk for days before he saw another living person.
"The ancients had great learning and made much use of machines. Machines pumped water into every dwelling through metal tubes, even to the tops of towers. People rode in flying boats faster than the fastest arrows. They even rode them to the stars, which are other worlds like this one. Subtle machines did their labor, drawing power from beams like sunlight but invisible and akin to lightning. But each machine needed men with special skills to take care of it, and it had to be told what to do. So when their keepers died, the machines became confused and soon they too began to die. And when the machines died that made the power, almost all the others died at once.
"And the people with the plague were seized with the desire to set fires, as a man with a cold must cough or sneeze. The few who survived inherited a smoking ruin.
"At first, they hoped that those who'd gone to the stars would come back someday and bring the machines back to life. But they never did, and it's probable that the plague struck them, too.
"One who survived was a trained psi named Jakob Tashi Norbu, who taught in a great place of learning called the University of Lucerne. In those days there was a powder that could be given to a person to tell whether or not he had psi potential, and he searched on foot through Europe, after the Death, looking for psis. He found three. He also searched the places of learning for psi tuners and found thirteen. Mine is one of them.
"It took him years.
"Father Jakob taught each of his psis and gave them tuners. They took mates and most of the children were psis. That was the beginning of the Alliance.
"Over the generations men's numbers increased, and lords and chiefs appeared. So the Alliance dispersed; it was becoming unsafe to be a separate community. Fourteen had psi tuners, and these worked themselves into the service of lords and chiefs as advisors. They kept their talents secret and used them to advance good lords or cause the fall of bad. Within the Alliance, those with psi tuners are called the Inner Circle. Over the centuries the Inner Circle has had an important influence on the ascension and the acts of rulers.
"Some without tuners also are advisors, and in most important towns there is at least one free merchant who is a psi. These we call the Kinfolk; some of us refer to the whole Alliance as the Kinfolk. And they, too, keep their talents a secret.
"Still others have become wanderers. We call them the Wandering Kin, but the peasants call them the Brethren. They wander through the countryside and among the villages as storytellers, teachers and magicians, speaking Anglic almost exclusively. This helps keep Anglic alive so that men of different lands can speak with each other. They awe the people by knowing their secrets and use their skills to seem supernatural. When available, the peasants call upon them to judge disputes. Their stories become traditions and their acts legends, and so far as their understanding and ability allows, they try to reduce the cruelty and injustice that men perpetrate on men.
"The Wandering Kin have their own tradition. They own nothing but the clothes they wear and a sleeping robe for when they must spend the night beside the road. The peasants feed and shelter them and give them clothes, regarding it a privilege. Only in unpeopled stretches do the Wandering Kin own even a hut, built by themselves in the wilderness, where they can shelter in bad weather."
Raadgiver also taught him how psis influence the thinking of non-psis. A psi cannot influence a subject to a conclusion or action incompatible with the subject's nature. But his reaction to a specific idea or event commonly can be modified. For example, the influence of a psi advisor on his feudal lord depends on:
1. Selection of a lord who is not particularly suspicious of him or adverse to advice, followed by the cultivation of the lord's confidence.
2. Sound insight into the lord's personality. An important element in psi training is training to interpret thoughts and emotions and to integrate them into a reasonable model of the subject's subconscious so his reactions can be predicted.
3. Correct reading of the lord's mood of the moment, which is automatic for a trained psi.
4. Ability to translate the psi's objective, or an approximation of it, into an objective harmonic with the lord's tastes or at least compatible with them.
Nils also was instructed in geography, map reading, and use of the psi tuner. Raadgiver also passed on odd bits and pieces of subjects from geology to philosophy. As far as possible, instruction and conversation were in Anglic.
The man Nils was to assassinate was a psi named Kazi. The Alliance had first become aware of him several decades earlier as the ruler of a powerful Near Eastern despotism. One of the Kinfolk equipped with a psi tuner had been sent to spy on him and was captured. Apparently he succeeded in suicide, however, for Kazi seemed to have gotten little information from him. But he clearly deduced the existence of a European psi organization. For a time Kazi had sent psi spies of his own into Europe, losing several but assassinating three of the Inner Circle. Apparently he concluded that so loose and nonmilitary an organization as the Alliance was no threat to him, for no more spies had been detected for a number of years.