The prescience, he realized, was an illumination that incorporated the limits of what it revealed- at once a source of accuracy and meaningful error. A kind of Heisenberg indeterminacy intervened: the expenditure of energy that revealed what he saw, changed what he saw.

And what he saw was a time nexus within this cave, a boiling of possibilities focused here, wherein the most minute action - the wink of an eye, a careless word, a misplaced grain of sand - moved a gigantic lever across the known universe. He saw violence with the outcome subject to so many variables that his slightest movement created vast shiftings in the patterns.

The vision made him want to freeze into immobility, but this, too was action with its consequences.

Prophecy and prescience — How can they be put to the test in the face of the unanswered question? Consider: How much is actual prediction of the “wave form” (as Muad’Dib referred to his vision-image) and how much is the prophet shaping the future to fit the prophecy? What of the harmonics inherent in the act of prophecy? Does the prophet see the future or does he see a line of weakness, a fault or cleavage that he may shatter with words or decisions as a diamond-cutter shatters his gem with a blow of a knife?

You cannot, you must not, judge the past by the present; you must try to see it in its own terms and values, if you are to have any inkling of it. You may not like what you see, but do not on that account fall into the error of trying to adjust it to suit your own vision of what it ought to have been.

I go to my past in order to discern the future.

One faces the future with one's past.

We observe things in the present and then, okay, we're assuming that that's always happened in the past, and we're going to figure out how this happened. You see? There is a difference between what you observed and what happened in the past.

"He can look ahead. See what's coming. He can — prethink. Let's call it that. He can see into the future. Probably he doesn't perceive it as the future." "No," Anita said thoughtfully. "It would seem like the present. He has a broader present. But his present lies ahead, not back. Our present is related to the past. Only the past is certain, to us. To him, the future is certain. And he probably doesn't remember the past, any more than any animal remembers what happened." "As he develops," Baines said, "as his race evolves, it'll probably expand its ability to prethink. Instead of ten minutes, thirty minutes. Then an hour. A day. A year. Eventually they'll be able to keep ahead a whole lifetime. Each one of them will live in a solid, unchanging world. There'll be no variables, no uncertainty. No motion! They won't have anything to fear. Their world will be perfectly static, a solid block of matter." "And when death comes," Anita said, "they'll accept it. There won't be any struggle; to them, it'll already have happened."

Study the past if you would define the future.

"How can I tell," said the man, "that the past isn't a fiction designed to account for the discrepancy between my immediate physical sensations and my state of mind?"

We must look upon what is to occur as having already occurred, and see nothing but the present in the future, for the future is but the present a little farther on.

Future and past blurred; what he had already experienced and what he would eventually experience blended so that nothing remained but the moment.

How can I tell," said the man, "that the past isn't a fiction designed to account for the discrepancy between my immediate physical sensations and my state of mind?

If we want to understand the past we must do so on its own terms, and disregard the future of that past, but if we want to understand the present we better not disregard the past steps that were essential for getting to the present. This is of importance especially for those of us engaged in trying to push ahead the scientific path of discovery today. We are not much interested in what scientists did wrong, there is too much of that. We are interested in what they did right, because we are trying to copy them in this, not in that.

A preoccupation with the future not only prevents us from seeing the present as it is but often prompts us to rearrange the past. (1954), p. 75