They all remained very silent.
“I see I have your attention,” Darkness said with ‘a slightsmile. But it was a smile that had no amusement in it whatsoever. “In the past,”he said, “I have interfered, in one way or another, in each of your lives.Except, of course, for you, Mr. Travers, as we have never met before. Your rolein what is about to happen will be minimal. Whereas theirs”-he indicated theothers with a sweeping motion of his walking stick-“will be pivotal and crucial.You doubtless have questions that you’d like to ask, but I’m afraid that I haveneither the time nor the liberty to answer them right now. However,” hecontinued, addressing his comments to the others, “everything that I have doneup to this point has had a purpose.
“There is a great deal that I simply cannot tell you,” hewent on, “but I can tell you this-something has occurred in the time periodfrom which I came that has resulted from a series of pivotal events that tookplace in the past. Not all of those events involve you, but some of the mostsignificant ones do. And this one is, perhaps, the most significant.”
“Will it be the last?” asked Andre softly.
“That all depends, Miss Cross,” Darkness replied. “If wepass this test-and it is very much a test, for you as well as me-then therewill be at least one more challenge that we shall have to face together. But ifwe fail here and now, then it will all be moot, for I will have only one chanceto attempt to set things right. Because, as you were saying just a few momentsago, to risk attempting it a second time would create a temporal paradox and theconsequences of that would be dire, indeed. For we are already involved in one,you see. In a manner of speaking.”
“What do you mean, in a manner of speaking?” asked Delaney.
“I cannot tell you all the details of what is about tohappen,” Darkness said, “but Steiger has guessed correctly. The Special OperationsGroup from the parallel universe has indeed created a temporal paradox by theiractions in this scenario. Had they done so in their own timeline, they wouldhave risked bringing about a timestream split. But they have done it in our timeline.which changes the situation considerably.”
“I’m not sure I see how,” said Travers. “If they sent inObservers through the confluence point who then returned and made their report,then by sending through an S.O.G. team and having them clock back and interferewith temporal continuity during the same period their Observers had reportedon, then the minute their Observers return, they will have altered their ownpast.”
“Not necessarily,” said Darkness. “Not if the Observers donot return.”
“What?” said Lucas. “You’ve lost me. They would have had tohave returned in order to make their report, so the S.O.G. team could comethrough and act on it. Because if they didn’t return and make theirreport, then how could the S.O.G. team have received it in the first place? It’sthe Grandfather Paradox.”
“Precisely,” Darkness said. “So let us use that as anexample. Assume that you clock back into the past in an attempt to kill yourgrandfather before he ever met your grandmother and you succeed in doing so.Your grandfather has now died before he could sire your father, which wouldhave made it impossible for you to have been born. If you had not been born,then how could you possibly have gone back into the past to kill yourgrandfather? The most basic problem in temporal physics. Seemingly insoluble.Only Mensinger had solved it. His solution, of course, was the timestreamsplit. however. Mensinger had not anticipated a Grandfather Paradox that couldinvolve two separate universes. And this is precisely what we are confrontedwith.
“Let us now take our particular example of the Grandfather Paradoxand follow it through using the two separate timelines,” Darkness continued. “Stepone: the people in the parallel universe locate a confluence point and sendObservers through in order to research as thoroughly as possible the temporalscenario they wish to disrupt. Step two: the Observers complete their task, goback through the confluence point to their own timeline. and make their report.Step three: a team is assembled from your counterparts in the parallel universe,the Special Operations Group, and sent through the confluence back to thescenario the Observers had already reported on. Of course, since they are goingback into a past scenario into which they had already sent Observers, those Observersare still going to be here when they arrive, because they will not yet havefinished their task and made their report. And if at that point the S.O.G. teamdoes anything to disrupt the original scenario, then obviously that will affectthe scenario, changing it from what the Observers had originally reported on.You with me so far’?”
“Right,” said Lucas.
The others mumbled their assent or nodded.
“All tight, then.” Darkness said, we understand that the momentthe S.O.G. team arrives here, then the moment they do Anything that affectsthis scenario, they change the past. They change what their Observers hadoriginally seen. And at that point, they create a temporal paradox. So in orderto avoid that, they proceed immediately upon arrival to step four. They killtheir own Observers.”
“Wait a minute,” Travers said. frowning. That wouldn’t work.Then they’d still be faced with a paradox. Their Observers had to havemade their report in the first place in order for the S.O.G. to receive and acton it.”
“You’re absolutely right,” said Darkness. Now they’re facedwith the hypothetical dead grandfather. Only in this case, he’s been killed inanother timeline. So what they’ve done has not affected their timeline at all.”
But it would still affect them,” insisted Travers. “The oneswho did the killing. I mean. The paradox still exists.”
“You’re quite right,” Darkness replied. “And it centersaround them. Only they are no longer in their own timeline.”
“I can’t see what difference that makes.” said Travers.
“Can’t you? Follow it through. What has actually occurred intheir own timeline? They sent Observers through a confluence point. That doesn’tchange. Their Observers completed the task they were sent out to do and cameback to make their report.”
“That does change.” Travers said. “The team went back andkilled them, so now they never come back.”
“Correct,” said Darkness. “But let’s get back to theiroriginal scenario. After the Observers made their report. The team went throughthe confluence point to effect their disruption. So what do we have so far?Observers leave on their mission. They come back and report. The S.O.G. teamleaves on its assignment Only part of their assignment is to kill theObservers, so now they can’t come back. The grandfather has been killed. So nowthe grandson can’t possibly exist. Only he does exist. Not in his own timeline.but in ours, where he doesn’t really constitute a paradox. The temporal paradoxwould only come into play when he went home again, back to his own timeline.Because then we’d have an S.O.G. team that would be returning to a universewhere their actions in ours had changed the past in theirs. As a result of whatthey’d done. their Observers never returned. And since their Observers neverretur
ned. the S.O.G. team never would have left. So they can’t return.either.”
“I’ll be damned,” said Travers slowly. He moistened his lipsnervously and nodded. “It works. So long as they don’t go back, there’s notemporal paradox in their own timeline.” He shook his head with awe. “It’spositively brilliant. They came here on a suicide mission!”
“No, they didn’t.” Lucas said quietly.
Travers glanced at him. “But then, how …”
“They just came here on a one-way trip,” said Lucas.
“They can never go back. But they can go anywhere they wantto in our timeline.”
“A guerrilla disruption team,” Steiger said. “They can spendthe rest of their lives clocking through our timeline. disrupting our historyeverywhere they go. And since they can never go home again, they’ve got nothingleft to lose.”