They shook their heads no.
"All right. It is very important we recover the Professor while he is still at the monastery. If he moves to either Castelgard or La Roque, it will be much more difficult. We have a tight mission profile. I expect to be on the ground between two and three hours. We will stay together at all times. If any of us is separated from the others, use your earpieces to get together again. We will find the Professor, and come right back. Okay?"
"Got it."
"You'll have two escorts, myself and Victor Baretto, over there in the corner. Say hello, Vic."
The second escort was a surly man who looked like an ex-marine - a tough and able man. Baretto's period clothes were more peasantlike, loose-fitting, made of a fabric like burlap. He gave a nod and a slight wave. He seemed to be in a bad mood.
"Okay?" Gomez said. "Other questions."
Chris said, "Professor Johnston has been there three days?"
"That's right."
"Who do the locals think he is?"
"We don't know," Gomez said. "We don't know why he left the machine in the first place. He must have had a reason. But since he is in the world, the simplest thing for him would be to pose as a clerk or scholar from London, on a pilgrimage to Santiago de Compostela in Spain. Sainte-Mère is on the pilgrimage route, and it is not unusual for pilgrims to break their trip, to stay a day or a week, especially if they strike up a friendship with the Abbot, who is quite a character. The Professor may have done that. Or he may not. We just don't know."
"But wait a minute," Chris Hughes said. "Won't his presence there change the local history? Won't he influence the outcome of events?"
"No. He won't."
"How do you know?"
"Because he can't."
"But what about the time paradoxes?"
"Time paradoxes?"
"That's right," Stern said. "You know, like going back in time and killing your grandfather, so that you can't be born and couldn't go back and kill your grandfather - "
"Oh, that." She shook her head impatiently. "There are no time paradoxes."
"What do you mean? Of course there are."
"No, there aren't," came a firm voice behind them. They turned; Doniger was there. "Time paradoxes do not occur."
"What do you mean?" Stern said. He was feeling put out that his question had been so roughly treated.
"The so-called time paradoxes," Doniger said, "do not really involve time. They involve ideas about history that are seductive but wrong. Seductive, because they flatter you into thinking you can have an impact on the course of events. And wrong, because of course, you can't."
"You can't have an impact on events?"
"No."
"Of course you can."
"No. You can't. It's easiest to see if you take a contemporary example. Say you go to a baseball game. The Yankees and the Mets - the Yankees are going to win, obviously. You want to change the outcome so that the Mets win. What can you do? You're just one person in a crowd. If you try to go to the dugout, you will be stopped. If you try to go onto the field, you will be hauled away. Most ordinary actions available to you will end in failure and will not alter the outcome of the game.
"Let's say you choose a more extreme action: you'll shoot the Yankee pitcher. But the minute you pull a gun, you are likely to be overpowered by nearby fans. Even if you get off a shot, you'll almost certainly miss. And even if you succeed in hitting the pitcher, what is the result? Another pitcher will take his place. And the Yankees will win the game.
"Let's say you choose an even more extreme action. You will release a nerve gas and kill everyone in the stadium. Once again, you're unlikely to succeed, for all the reasons you're unlikely to get a shot off. But even if you do manage to kill everybody, you still have not changed the outcome of the game. You may argue that you have pushed history in another direction - and perhaps so - but you haven't enabled the Mets to win the game. In reality, there is nothing you can do to make the Mets win. You remain what you always were: a spectator.
"And this same principle applies to the great majority of historical circumstances. A single person can do little to alter events in any meaningful way. Of course, great masses of people can 'change the course of history.' But one person? No."
"Maybe so," Stern said, "but I can kill my grandfather. And if he's dead then I couldn't be born, so I would not exist, and therefore I couldn't have shot him. And that's a paradox."
"Yes, it is - assuming you actually kill your grandfather. But that may prove difficult in practice. So many things go wrong in life. You may not meet up with him at the right time. You may be hit by a bus on your way. Or you may fall in love. You may be arrested by the police. You may kill him too late, after your parent has already been conceived. Or you may come face to face with him, and find you can't pull the trigger."
"But in theory . . ."
"When we are dealing with history, theories are worthless," Doniger said with a contemptuous wave. "A theory is only valuable if it has the ability to predict future outcomes. But history is the record of human action - and no theory can predict human action."
He rubbed his hands together.
"Now then. Shall we end all this speculation and be on our way?"
There were murmurs from the others.
Stern cleared his throat. "Actually," he said, "I don't think I'm going."
Marek had been expecting it. He'd watched Stern during the briefing, noticing the way he kept shifting in his chair, as if he couldn't get comfortable. Stern's anxiety had been steadily growing ever since the tour began.