Chas shook his head. “I can’t see it. Like Harry said, you’ve got two left. It’s either one or the other. We don’t know which, even if you might. So how can anything we decide make a difference?” Harry seemed less sure, but at the same time completely unsure why. He rubbed his chin and stared at the two face-down cards as if waiting for a revelation.
Kieran studied their faces, as if divining the way to play a poker hand. “When you made your choice, the odds were one in three that it was the right one,” he offered. “That can’t have changed. So the odds for the other card here—the one you didn’t pick—must be two in three. Change your choice and you double your chances.”
Chas brooded, then shook his head again. “That was then. This is different. We’ve got two cards. It’s fifty-fifty.”
From the entry chamber that served the cabin’s three rooms came the sound of the pump starting up to fill the outside lock. Juanita had pushed her glasses down her nose and was following the conversation over the paper she had been reading. “Think of it this way,” she suggested. “Suppose your first choice had been out of the whole pack instead of just three cards. Kieran knows which is the king. He’s used that knowledge to throw out fifty for you and left just the king and one other. Do you still think the king is likely to be the one you picked?”
Light dawned in Harry’s eyes. “Ri-ght! Now I see it!” It was Chas’s turn to look uncertain.
Before it could go any further, the sound of boots stamping and dust being brushed off a suit came from outside the room. Then the door opened and Dennis came in, already removing his helmet. He was in his early thirties, sandy-haired with a fresh, open face, the kind of pragmatic academic who preferred getting out in the world and doing things rather than theorizing. His preoccupation with his work left him with a total disinterest in politics, which with his generally amiable nature meant he got along with just about anybody. Dennis had worked with Trevany previously on Earth. For the past couple of years, however, he and Jean Graas had been exploring various parts of the Martian surface with Hamil and Juanita.
“How are things going?” Juanita asked him.
“Steady. Shayne and Zeke have cleared the top of the E-2 object. It’s definitely a gate. The amazing thing is, it’s monolithic. Walter estimates that on Earth that one piece would weigh over two hundred tons. And places we know back there have designs just like it.”
Chas leaned back from the table and spread his hands. “So how did they build with things like that? I mean, I’ve worked on enough construction projects to know what it takes. I’ve heard these stories about how they were supposed to have done it with lots of guys hauling ropes, but with me it doesn’t wash. Once something like those things is down, it’s down. So how could they end up with them put together like stacking toys?”
“There was an Inca king who wondered the same thing,” Juanita commented. “So he decided to see if he could emulate it by bringing just one boulder of comparable size to add to the citadel at Sacsayhuaman in Peru. According to a Spanish account from the sixteenth century, he had twenty thousand Indians hauling it across the mountains. It broke loose over a precipice and crushed something like three thousand men. That was the end of the experiment—their only known attempt to duplicate the feats they’re supposed to have achieved all over the area. Not very convincing, you see.”
“You mean that whatever the original techniques were, the Incas of that time had no knowledge or experience of them,” Kieran translated.
“Exactly,” Dennis said. “And now this. It gets more interesting, doesn’t it?”
Just then, the call beep sounded from the c-com unit on the wall near where Juanita was sitting. She reached across to accept. The screen showed the head and shoulders of Walter Trevany, inside the Juggernaut, which was now drawn alongside the cabin and connected by a short, flexible-wall tunnel to avoid the hassle of suiting up every time somebody needed to get from one to the other. His expression was uncertain, with a hint of worry. “Just to let you know, we picked up something approaching on radar a few minutes ago,” he announced. “It looks like we might be having visitors. I don’t know who. Hamil’s on his way up from the Hole. If anyone else wants to show their face, we’ll see you outside.”