“Math, logic, and physics are universal. So I guess that is the only thing aliens can talk with us about.”

“But they are only the beginning of the Monument message. What of other universals? But how do you make a symbol for honesty, for justice, for beauty, for love, for any abstraction?”

“Maybe those things come out of genetic adaptation to game-theory: organisms that don’t play fair enough to cooperate with natural allies can’t compete with mutual foes.”

“No,” she said, “I don’t believe it is merely game-theory. Or, I should say, what is game-theory based on? How do we teach our own children abstractions like truth and justice? Toddlers learn about right and wrong, about yes and no, forbidden and permitted, the basics of law and mercy, long before they learn to count. We do not teach them biology, then genetics, then the theory of the selfish Gene, then the theory of the natural harmony of self-interest, and then tell them it is not in their self-interest not to fib to their fathers. When a child is caught lying, what do you do?”

He straightened up and stepped away from the mirror, partly because the nearness was driving him mad, partly because he wanted to look at her face.

“Lecture ’em good, and take a strap to ’em, so to help remember them the lecture.”

“And what does that suggest?”

“Well—I reckon our kids learn universal concepts the way a baby bird learns birdsongs,” Montrose said. “Pain and pleasure mean ‘yes’ and ‘no.’ The signs we show them, simple things at first, like a swat on the rump, match like lock and key to something in their nervous system. Swat on the rump stimulates the pain centers wired to signal an avoid this behavior. Smiles and touches linked to ganglia wired up to express pleasure. Lock fits key.”

“Then how is it possible to talk to aliens?”

“I am not sure it is. No alien creature, things whose bodies are made of silicon rocks or methane soup or intelligent clouds of smog, things we can’t imagine, they are not going to have any locks in their brains—or whatever part of them does their thinking and fretting—that can possibly fit our keys. Our notions of justice and truth and beauty don’t mean spittle to them. How could you make a language to express things like that? Ideas that only make sense in a certain context? Except…” Menelaus frowned thoughtfully. “Same way we teach our babies, I guess. Teach them in context. Point and grunt. Swat then on the rump. Give a petting and a smile. But you would have to give them our nervous system first.”

“You think as I do. Go on.”

“Go on to what?” He said, exasperated. “You can’t send the context of the message before you send the message! What would that even mean? A language that deciphers itself? How do you do it?”

She smiled, and it was like the sun coming out.

“Simple. You encode the lock and the key both,” she continued. “The human brain is not really a lump of hydrogen and carbon, is it? It is a pattern of information. Anything that you grew in a tank that followed the code-pattern of the human genome would be human, would it not? A human brain made of another substance, provided the nerve cells operated in the same way, or in a way parallel to ours, would be human, would it not?”

“Ghost Del Azarchel thinks so, or so he told me.”

“And what is the human genome but a language, a code of information, a song of four notes, which could be recompiled into any system of other notes, the way a number line can be expressed in base two or base ten?”

He nodded. “I guess so. If you were intelligent, and you wanted to send a message, and the only thing you knew about the recipient was that he occupied the same universe with the same natural laws as you, you’d send the message with the messenger. The messenger would be coded up, expressed as a series of numbers, or logic signs, or something else universal. You show him how to build the lock, tumbler by tumbler, and then you show him where to put all the ridges on the key, tooth by tooth. Is that what you are getting at with all this weird talk of logic and meta-logic? The Monument is instructions on how to build a system that can read the Monument.”

“Not a system to read the Monument. A system to build a person who can learn to read it.”

“A messenger!” He smacked his fist into his palm and grinned. “Listen, we can build this messenger, this message-reading machine. You must know that Del Azarchel has made a breakthrough in brain emulation. He has got a perfect replica of himself, I mean perfect, talks like him, and over the phone Alan Turing couldn’t tell it weren’t him. If you have enough wealth, Princess, then you can afford to get me the computer space needed to build a second one…”

“It is not necessary.”

“No, no, listen! It’s a great idea. All you do is string up the models the same way the human brain is strung up, using the universal life-code here, translated into human DNA, and making the hardwiring of the brain follow those DNA instructions … Don’t make a model of Blackie, make a model of the brain that can read the Monument, based on the Monument’s own negative image of…”

“I am saying it is not necessary.”

“… unlike a real brain, there is no upper limit to … Wait. Why ain’t it necessary?”

“It’s been done.”

Such a wild hope entered his heart at that moment, he wondered if he were going mad. The key to the Monument was what this conversation was about! The key to the future of Mankind, and, yes, to the future of Menelaus as well. If his soul had been music, it would have roared into a crescendo at that moment.

He understood what she was saying.

“It’s you, Princess, isn’t it? You are the key. You, the starry messenger!” Menelaus pointed at the Monument. “Where and how exactly were you born, Princess? What part of that describes your code?”

Rania looked at him in puzzlement for a moment, and then mirth began dancing in her eyes, and she threw back her head, and peals of girlish laughter rang and echoed throughout the corridor.

“Oh, dear, no … forgive me for laughing, but … ah! The irony…”

“You’re not the key to the Monument?”

“Would that I were!” And just as suddenly as her joy appeared, sorrow now appeared.

“Well, who else?”

“You are.”

“Me?”

“You, Crewman Fifty-One, you. Don’t you see the connection?”

“Nope.”

“For a genius, you are not very bright.” She pointed back at the mirror. “Compare these two files. Don’t you see those are two different translations of the same thing, defined by the same algorithm?”

The first file was the Zurich run again. He had derived those parameters, of course, from the Monument math itself, manipulating symbols whose meaning he did not know, merely trusting that the unknown “grammar rules” of the aliens would make the conclusion valid if the axioms were valid.

The second file was a snapshot of the Theta sine symbol group of the Monument: a mathematical expression which, when translated into Earthly biochemistry, contained instructions on how to build or emulate a brain to read the Monument.

The two were the same. In using the Monument math to establish which nerve connections to use to become intelligent enough to read the Monument, Menelaus had unwittingly come to the same logic-path as the Monument instructions on how to read the Monument.

She said, “The pattern is an emergent property of the mathematics.”

“Why did they put the same thing in two places? I was not using the symbol-forms from that segment to do my brain-tinkering!”

“The Monument Builders are obsessed with recursions.”

Menelaus understood. The builders were trying to be as clear as possible, and so they repeated themselves. It was a communication strategy: two parts of a redundant message could be checked against each other for accuracy.

She said, “You did not know what you were doing to yourself, but you produced, in part of your cortex, something that follows this same pattern that repeats as a leitmotif in the Monument. Don’t you recall?”