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Carlotta got up and came to look over his shoulder. "It's not even language. It doesn't divide into words."
"That's deliberate," said Bean. "If it divided into words it would look like a message and invite decoding. The easy way that any amateur can decode language is by checking word lengths and the frequency of appearance of certain letter patterns. In Common, you look for letter groupings that could be 'a' and 'the' and 'and,' that sort of thing.
"And you don't even know what language it's in."
"No, but it's bound to be Common, because they know they're sending it to somebody who doesn't have a key. So it has to be decodable, and that means Common."
"So they're making it easy and hard at the same time?" "Yes. Easy for me, hard for everyone else."
"Oh, come now. You think this was written to you?"
"Ender. Dragon. I was in DragonArmy, unlike most of them. And whom else would they be writing to? I'm outside, they're in. They know that everyone is there but me. And I'm the only person that they'd know they could reach without tipping their hand to everybody else."
"What, did you have some private code?"
"Not really, but what we have is common experience, the slang of Battle School, things like that. You'll see. When I crack it, it'll be because I recognize a word that nobody else would recognize."
"If it's from them."
"It is," said Bean. "It's what I'd do. Get word out. This picture is like a virus. It goes everywhere and gets its code into a million places, but nobody knows it's a code because it looks like something that most people think they already understand. It's a fad, not a message. Except to me."
"Almost thou persuadest me," said Carlotta.
"I'll crack it before I go to bed."
"You're too little to drink that much coffee. It'll give you an aneurysm." She went back to her own mail.
Since the words weren't separated, Bean had to look for other patterns that might give things away. There were no obvious repeated two-letter or three-letter patterns that didn't lead to obvious dead ends. That didn't surprise him. If he had been composing such a message, he would have dropped