"That pulse is nothing more nor less than a feedback pulse indicating that an action matrix has been set up which is in non-conformity with the previously chosen pattern of learning or intent. It's a feedback alarm carrying the information that an error will result if the proposed action is carried out. When the feedback is successfully returned to the action matrix a change is made until there is no feedback and a correct action is taken. When the feedback is blocked or ignored, an error results. It's as simple as that! Your complex human being is nothing but a fairly elaborate cybernetic machine operating wholly on feedback principles. The only time he fails and breaks down is when he ceases to act like the cybernetic machine that he is!" * * * * * Holt's eyes shone triumphantly as he patted the long strips of paper on the table. Paul followed the motion of his hand and remained staring at the graphs in a kind of stunned recognition. There must be some mistake, there _had_ to be. Holt's interpretation was wrong, even if the data were correct. Man, a feedback response mechanism--! If that were true a vacuum tube structure could eventually be devised to do _anything_ a man could do. "I think we'll hold off on that dinner a while yet," Paul said. "The data are interesting and, I'm sure, important--but I can hardly agree with your conclusions." Inwardly, he cursed the stiltedness he felt creeping into his voice, and his irrational resentment of Holt's continued smug grin. "Take all the time you want," Holt said, "but when you're through you'll come up with the same answers I've got. Man is a machine and nothing else. Our only job now is to discover why the feedback sometimes fails, and to set it back on the job." Paul took the recordings and the analyzer graphs back to his own office. He called Barker and showed the older man what Holt had found out. "If this is true," he said, "we don't need to worry about validating Space Command's pre-chosen conclusions. It has already been done." Dr. Barker looked puzzled and a little frightened as he sat down at the desk to examine the charts. After an hour, he looked up. "It's true," he said. "There's no escaping the fact. Look what we have here--" He pointed to a corresponding sector of the six charts he'd lined up. "After the first feedback impulse, there was no attempt to correct," he said, "or, rather, there was a deliberate effort to suppress the feedback. This created a second, larger feedback, which, in turn resulted in increased suppression and a simultaneous enlargement of the error. The result was a hunting effect in increasingly large amplitude, like the needle of an autosyn indicator with undamped positive feedback.