Heads were already beginning to swivel.

“And I’ll enter the room… now.”

The doors opened and Griffin strode in, smiling jauntily and waving as he made his way to the stage.

The two identical men shook hands.

“Griffin, good to see you.”

“Good to see you, Griffin.” The earlier Griffin addressed the audience: “As you can see, it is indeed possible for the same object to be in two places at the same time.” He handed the later Griffin the microphone. “And now I must leave to take that limo I told you about earlier, because—well, I’ll let my one-hour-older self tell you why. With age comes wisdom, you know.”

Down the aisle Griffin went. He stooped to pick up the tennis ball along the way, and then disappeared through the double doors.

His other self reached into a pocket and set that same tennis ball atop the podium. “There goes the pragmatic resolution of our dilemma. By making a simple loop in time, I was able to witness the same moment from two different perspectives. Causality was not violated. There was no paradox involved.

“Similarly, all your actions in the past—all your future actions, everything you will do—have already existed for millions of years, and are a part of what led inevitably to this present moment. Don’t obsess about the repercussions of simple actions. Step on as many butterflies as you wish—the present is safe.

“However, suppose when I entered the room just now, I decided to behave differently than I had witnessed myself behaving the first time. Suppose that rather than shake hands, I’d decided to punch myself out. Suppose then my earlier self had become so irate that he refused to travel into the past. What then?”

“It couldn’t have happened!” somebody called from the audience. “It didn’t—so it couldn’t.”

“So common sense would tell you. However—slide!” The incomprehensible physical equations again filled the screen. “Common sense has very little to do with physics. Unhappily, paradox is only too possible.

“Let’s imagine that when I came into this room, with this tennis ball in my pocket, I kicked the original of it out of my way in the aisle, sending it skittering in among this amiable sea of friendly faces. This would have prevented my earlier self from picking it up in the first place. Where, then, would this tennis ball have come from? Suppose also that I subsequently took this ball and gave it to my earlier self to take back in time so I could bring it here to pass back into time.” He tossed the ball back and forth between his hands. “Where did it come from? Where does it go? If it came spontaneously into being, as a miracle of quantum physics, then why does it have the Spalding logo stamped into its side?”

Nobody laughed. A few in the audience cleared their throats uncomfortably.

“Either of those instances—the refusal to perform a previously witnessed act, or the tennis ball from nowhere—would have been a massive violation of cause and effect. There are extremely good reasons why this cannot be allowed to occur. I am not permitted even to hint at these reasons, but I can assure you that we take them very seriously indeed.

“The bottom line is simply this: Could you go back in time and kill your own grandfather? Yes and no. Yes, it could happen. There’s nothing in the physical nature of reality to prevent it. No, we won’t permit it to happen.

“We have means of detecting a paradox before it actually happens—and, again, I won’t tell you what they are. But any threat to this precious and fragile enterprise will be nipped in the bud, I can assure you that. And those responsible will be punished. No exceptions. And no clemency, either.”

He slipped the tennis ball back in his pocket. “Any questions?”

A spry old gent who might have been the father of someone Leyster once worked with, stood. “What if, in spite of your best efforts, a paradox slips by you?”

“The entire project would be canceled. Retroactively. By which I mean that this wonderful opportunity will then have never been placed before you. It’s harsh, but—I have been assured by those who know—absolutely necessary.”

A woman stood. “What would become of us, then?”

“Cut free from causality, our entire history from that moment onward would become a timelike loop and dissolve.”

“Excuse me. What does that mean?”

Griffin smiled. “No comment.”

Leyster thrust up his hand.

“Mr. Leyster. Somehow I knew that you would be one of those asking questions.”

“This technology—whatever it is—must be expensive.”

“Extremely so.”

“So why us?

“Is that a complaint?” Griffin asked. Amid laughter, he clamped a hand over his watch, glanced down, and then up again. “Any further questions?”

Leyster remained standing. “I just don’t understand why this technology is being made available for our use. Why paleontologists? Why not the military, the CIA…” He fumbled for another plausible alternative, “…politicians? We all know how little money was spent last year on fieldwork, worldwide. Why are we suddenly important enough to rate the big bucks?”

There were annoyed sounds from the audience.

Griffin frowned. “I fail to see why you’re opposed to this project.”

“I’m not—”

“No, listen to me! I’ve come here bearing the greatest gift that anyone has ever received, and it’s being presented to you at no cost whatsoever. Yes, there are a few strings attached. But, my God, they’re extremely light, and what you get—the opportunity to study real, living dinosaurs—is so extraordinary, that I’d think you’d be grateful!”

“I only—”

People were actually shouting at him now. The crowd belonged to Griffin. It was more than the fact that he controlled access to the one thing they all wanted more than anything else. He knew how to manipulate them. A salesman had once told Leyster that the first thing he did was to find out a prospect’s name. Once the name was dropped into the spiel, he said, the prospect was halfway to being sold. What Griffin was doing was more complex than that. But no more sincere.

They don’t want to know, he thought. They’ve received something they know they don’t deserve, and they’re not willing to ask the price. They’re afraid it might be too high. “I really feel that we—”

“Sit down!” somebody shouted.

Blushing with confusion, he sat.

Griffin held up both hands for calm. “Please. Please. Let’s remember that in science, no questions are forbidden. Our Mr. Leyster had a perfect right to ask. Unfortunately, reasons of security prevent me from answering. Now, as I mentioned before, there will be films tonight, and if you’ll look at your schedules, you’ll see that you have three hours for dinner. I must ask you not to leave the hotel.

“In the meantime—a lot of you have been working with materials provided from the Mesozoic past. Let’s hear those papers.”

The applause was enthusiastic. Griffin leaned forward into it, almost bowing.

After lunch, Leyster returned to the Grand Ballroom for the afternoon keynote. He looked around for the Metzgers. Only a few of the seats were filled, but there were plenty of people in the back of the room, networking and politicking, leaning against walls and looking skeptical, speaking earnestly up at those leaners, and reaching into paper bags to bring forth the polished skull of a troodontid or the brightly feathered wing and toothed beak of an Archaeopteryx.

There was no use trying to be a part of the influence-swapping until he sorted out who was who, the major players from the bright young grad students who would hang in for a season or three before realizing that the money was elsewhere, the influential patriarchs of major institutions who spent so much time in administration they never published anything from the shy nondescripts who averted their heads to hide the eyes that burned with passionate insight.