David gave a thin smile. “I thought you were at war with the UN.”
“We are. But, let’s just say that some of us are concerned about what might happen after the war. The paper you wrote in prison was…intriguing.”
“John Bunyan wrote Pilgrim’s Progress in prison. It’s nice to have a hobby, something to pass the time.”
“‘On a New Interpretation of the Fermi Paradox,’” Warhurst said. “That’s not exactly Pilgrim’s Progress.”
“Pilgrim’s Progress is a morality play about making it into heaven. My paper deals with the possible extinction of humankind. There’s a difference.”
“Indeed.” He nodded to his aide, who unholstered a PAD and began making entries. “So. Tell us about Fermi’s Paradox?”
“Back in the 1940s, Enrico Fermi—he was an important physicist who did a lot of the early work on atomic energy—asked the question ‘Where are they?’ He was asking about other intelligent life in the galaxy.”
“He meant…why haven’t we seen them?”
“Exactly. You see, our galaxy is something like eight billion years old…about twice as old as Earth itself. It took less than four billion years for life to evolve here; since we know that planets are pretty common, it’s fair to assume that life, including intelligent life, has evolved before, time after time after time. Fermi was making these assumptions before we knew about the Cave of Wonders, of course. He thought the galaxy ought to be crawling with other civilizations.”
“Lovely thought.”
“It gets better. It’s been demonstrated that if even one intelligent race evolves, in all the history of the galaxy, and if that race has the same sort of exploratory yearnings, the same curiosity and drive and determination to reach out into space that we do, it could actually colonize the entire galaxy in a ridiculously short period of time.”
“How short?”
“Depends. Even if they never were able to build ships that went more than a few percent of the speed of light, though, they could still reach every star, colonize every habitable world, even do their equivalent of terraforming to every likely planet in the galaxy in less than three million years….”
“Three million years is a long time.”
“It’s an eyeblink, compared to eight billion years.”
“I see what you mean. So Fermi wondered why somebody hadn’t already colonized the entire galaxy. Why they weren’t here already.”
“Exactly. And the more we learn about extraterrestrial civilizations, the more urgent his question becomes. In the Cave of Wonders, beneath Cydonia…that huge array of image screens shows hundreds of other civilizations. We suspect that the blank screens in the Cave represent civilizations that no longer exist, that have died out over the past half million years. Extraterrestrial cultures are common. The galaxy should have been filled up many times over. It should be teeming with starfaring civilizations. Radio astronomers ought to be bombarded by the alien equivalent of TV programs, shortwave broadcasts, and military call signs. But when we listen, we hear…nothing.”
“But we do know there are other races out there. And we know that at least two of them were here, once.”
“Right. But what happened to them?
“According to your research both of them were attacked. Destroyed by invaders?”
“You’ve seen photos of the Cydonian site, General?” When Warhurst nodded, David went on. “You know, there are still people who haven’t been there who argue that the Face on Mars is a natural phenomenon, that the fact that the Cave of Wonders is located underneath is just a coincidence. It was assumed to be a chance product of weathering for a long time after it was first spotted by early orbital probes. And the funny part was, the first detailed imaging orbital of the site, in the late nineties, showed it really didn’t look much like a face at all. You can just barely make out the overall shape of the features, but they’re battered, smashed, broken…and what’s left has been worn down to dust and rubble by half a million years of sandstorms. The earlier, lower-quality images had actually blurred things enough to show what the Face must have looked like once, half a million years ago, before someone, or something, shot the hell out of it.”
“Okay, so what’s the point of your new explanation of Fermi’s Paradox?” Warhurst asked. “I mean, what we’ve found on Mars and the Moon, especially the display screens in the Cave of Wonders, proves that aliens were here. What’s the paradox?”
“Mostly, I guess, the paradox is why aren’t they here now? Some of the astronut cults make the claim that we are the descendants of alien colonists, maybe an expedition of Builders who got marooned here a long time ago, but that just doesn’t hold up. Our DNA is very clearly the product of evolution here on Earth. Over 98 percent of the DNA in chimps is identical to ours.