What followed was, in the ordinary sense of the word, an illusion, since no one but someone who was aided by the mentalic power of a well-trained Second Foundationer would have been able to detect anything at all, either by the senses or by any physical detecting device.
It was the building up of a face and its appearance from the contours of a mind, and even the best mentalist could succeed in producing only a shadowy and somewhat uncertain figure. Compor's face was there in mid-space, as though it were seen through a thin but shifting curtain of gauze, and Gendibal knew that his own face appeared in an identical manner in front of Compor.
By physical hyperwave, communication could have been established through images so clear that speakers who were a thousand parsecs apart might judge themselves to be face-to-face. Gendibal's ship was equipped for the purpose.
There were, however, advantages to the mentalist-vision. The chief was that it could not be tapped by any device known to the First Foundation. Nor, for that matter, could one Second Foundationer tap the mentalist-vision of another. The play of mind might be followed, but not the delicate change of facial expression that gave the communication its finer points.
As for the Anti-Mules - Well, the purity of Novi's mind was sufficient to assure him that none were about.
He said, "Tell me precisely, Compor, the talk you had with Trevize and with this Pelorat. Precisely, to the level of mind."
"Of course, Speaker," said Compor.
It didn't take long. The combination of sound, expression, and mentalism compressed matters considerably, despite the fact that there was far more to tell at the level of mind than if there had been a mere parroting of speech.
Gendibal watched intently. There was little redundancy, if any, in mentalist-vision. In true vision, or even in physical hypervision across the parsecs, one saw enormously more in the way of information bits than was absolutely necessary for comprehension and one could miss a great deal without losing anything significant.
Through the gauze of mentalist-vision, however, one bought absolute security at the price of losing the luxury of being able to miss bits. Every bit was significant.
There were always horror tales that passed from instructor to student on Trantor, tales that were designed to impress on the young the importance of concentration. The most often repeated was certainly the least reliable. It told of the first report on the progress of the Mule before he had taken over Kalgan - of the minor official who received the report and who had no more than the impression of a horselike animal because he did not see or understand the small flick that signified "personal name." The official therefore decided that the whole thing was too unimportant to pass on to Trantor. By the time the next message came, it was too late to take immediate action and five more bitter years had to pass.
The event had almost certainly never happened, but that didn't matter. It was a dramatic story and it served to motivate every student into the habit of intent concentration. Gendibal remembered his own student days when he made an error in reception that seemed, in his own mind, to be both insignificant and understandable. His teacher - old Kendast, a tyrant to the roots of his cerebellum - had simply sneered and said, "A horselike animal, Cub Gendibal?" and that had been enough to make him collapse in shame.
Compor finished.
Gendibal said, "Your estimate, please, of Trevize's reaction. You know him better than I do, better than anyone does."
Compor said, "It was clear enough. The mentalic indications were unmistakable. He thinks my words and actions represent my extreme anxiety to have him go to Trantor or to the Sirius Sector or to any place but where, in fact, he is actually going. It meant, in my opinion, that he would remain firmly where he was. The fact that I attached great importance to his shifting his position, in short, forced him to give it the same importance, and since he feels his own interests to be diametrically opposed to mine, he will deliberately act against what he interprets to be my wish."
"You are certain of that?"
"Quite certain."
Gendibal considered this and decided that Compor was correct. He said, "I am satisfied. You have done well. Your tale of Earth's radioactive destruction was cleverly chosen to help produce the proper reaction without the need for direct manipulation of the mind. Commendable!"
Compor seemed to struggle with himself a short moment. "Speaker," he said, "I cannot accept your praise. I did not invent the tale. It is true. There really is a planet called Earth in the Sirius Sector and it really is considered to be the original home of humanity. It was radioactive, either to begin with or eventually, and this grew worse till the planet died. There was indeed a mind-enhancing invention that came to nothing. All this is considered history on the home planet of my ancestors."
"So? Interesting!" said Gendibal with no obvious conviction. "And better yet. To know when a truth will do is admirable, since no nontruth can be presented with the same sincerity. Palver once said, "The closer to the truth, the better the lie, and the truth itself, when it can be used, is the best lie."
Compor said, "There is one thing more to say. In following instructions to keep Trevize in the Sayshell Sector until you arrived - and to do so at all costs - I had to go so far in my efforts that it is clear that he suspects me of being under the influence of the Second Foundation."
Gendibal nodded. "That, I think, is unavoidable under the circumstances. His monomania on the subject would be sufficient to have him see Second Foundation even where it was not. We must simply take that into account."
"Speaker, if it is absolutely necessary that Trevize stay where he is until you can reach him, it would simplify matters if I came to meet you, took you aboard my ship, and brought you back. It would take less than a day..."