Prelude to Foundation

He said, “Not quite, actually. What I have done is much more limited than that. In many systems, the situation is such that under some conditions chaotic events take place. That means that, given a particular starting point, it is impossible to predict outcomes. This is true even in some quite simple systems, but the more complex a system, the more likely it is to become chaotic. It has always been assumed that anything as complicated as human society would quickly become chaotic and, therefore, unpredictable. What I have done, however, is to show that, in studying human society, it is possible to choose a starting point and to make appropriate assumptions that will suppress the chaos. That will make it possible to predict the future, not in full detail, of course, but in broad sweeps; not with certainty, but with calculable probabilities.”

The Emperor, who had listened carefully, said, “But doesn’t that mean that you have shown how to predict the future?”

“Again, not quite. I have showed that it is theoretically possible, but no more. To do more, we would actually have to choose a correct starting point, make correct assumptions, and then find ways of carrying through calculations in a finite time. Nothing in my mathematical argument tells us how to do any of this. And even if we could do it all, we would, at best, only assess probabilities. That is not the same as predicting the future; it is merely a guess at what is likely to happen. Every successful politician, businessman, or human being of any calling must make these estimates of the future and do it fairly well or he or she would not be successful.”

“They do it without mathematics.”

“True. They do it by intuition.”

“With the proper mathematics, anyone would be able to assess the probabilities. It wouldn’t take the rare human being who is successful because of a remarkable intuitive sense.”

“True again, but I have merely shown that mathematical analysis is possible; I have not shown it to be practical.”

“How can something be possible, yet not practical?”

“It is theoretically possible for me to visit each world of the Galaxy and greet each person on each world. However, it would take far longer to do this than I have years to live and, even if I was immortal, the rate at which new human beings are being born is greater than the rate at which I could interview the old and, even more to the point, old human beings would die in great numbers before I could ever get to them.”

“And is this sort of thing true of your mathematics of the future?” Seldon hesitated, then went on. “It might be that the mathematics would take too long to work out, even if one had a computer the size of the Universe working at hyperspatial velocities. By the time any answer had been received, enough years would have elapsed to alter the situation so grossly as to make the answer meaningless.”

“Why cannot the process be simplified?” Cleon asked sharply.

“Your Imperial Majesty,”-Seldon felt the Emperor growing more formal as the answers grew less to his liking and responded with greater formality of his own, “consider the manner in which scientists have dealt with subatomic particles. There are enormous numbers of these, each moving or vibrating in random and unpredictable manner, but this chaos turns out to have an underlying order, so that we can work out a quantum mechanics that answers all the questions we know how to ask. In studying society, we place human beings in the place of subatomic particles, but now there is the added factor of the human mind. Particles move mindlessly; human beings do not. To take into account the various attitudes and impulses of mind adds so much complexity that there lacks time to take care of all of it.”

“Could not mind, as well as mindless motion, have an underlying order?”

“Perhaps. My mathematical analysis implies that order must underlie everything, however disorderly it may appear to be, but it does not give any hint as to how this underlying order may be found. Consider-Twenty-five million worlds, each with its overall characteristics and culture, each being significantly different from all the rest, each containing a billion or more human beings who each have an individual mind, and all the worlds interacting in innumerable ways and combinations! However theoretically possible a psychohistorical analysis may be, it is not likely that it can be done in any practical sense.”

“What do you mean ‘psychohistorical’?”

“I refer to the theoretical assessment of probabilities concerning the future as ‘psychohistory.’ ”

The Emperor rose to his feet suddenly, strode to the other end of the room, turned, strode back, and stopped before the still-sitting Seldon. “Stand up!” he commanded.

Seldon rose and looked up at the somewhat taller Emperor. He strove to keep his gaze steady.

Cleon finally said, “This psychohistory of yours… if it could be made practical, it would be of great use, would it not?”