"Yes. All I ask in return is your promise not to try to undo anything, and to go ahead with your work without ever mentioning what has happened. Once you give your promise, I will let you and Nadine go to your time and stay there, free agents."

Earl frowned. "I don't get it," he said. "I didn't expect anything like this from you."

"You thought that after I had by-passed you and accomplished my purpose I would eliminate you?" The Cyberene laughed. "You will find that I'm a very benevolent master." The video eyes seemed to glisten with joviality.

"I still don't get it," Earl said, puzzled. "You want my word that I won't interfere with anything you do from here on in."

"Yes. After all, there is a lot to do yet before the Brain in your time stream is activated. I must—"

"So!" Earl interrupted. "According to your theory of time that you so carefully explained to me, the discovery of the vital nerve substance should have fixed up everything. It didn't."

"The Brain hasn't been activated yet in your time stream. When it has, then the future will reshape itself."

"I want to understand," Earl said. "As I understand it, some act, some crucial act, must be changed from the way it happened in the past—in my future in that past. Until that crucial moment is changed from the way it happened, all the future stemming from it remains unaltered. The instant that crucial moment is changed, presto—the whole future from 1980 right down to 3042 does a mighty flip flop and right here and now, in that other Earth so close to this one, things will change as abruptly as the change of scene on a screen."

"That's correct."

"Then getting my lab reports correct wasn't the thing. There is still something to come, back there, that must be changed? In spite of everything up to now, you are still facing defeat? That's why you are willing to offer me so much?"