The Unseen World (40 page)

Gregory took the receipt back. Studied it. A light moved across his face.

“Do you have any ideas at all?” Gregory asked.

“Not really,” Ada said. “The consensus is either that David wasn't in his right mind when he created it, or that he made it using a one-time pad.”

And as she said it, she lifted from the table the floppy disk Gregory had brought her. She studied it.

It had been years since she had broken an encryption, but she still recognized the buzzing, electric feeling of being on the cusp of undoing one—she had first felt it as a child, with David next to her, guiding her—and it overtook her now. She felt light-headed.

“Do you see it?” said Gregory.

T
here were fifty-three letters in the encryption.

DHARSNELXRHQHLTWJFOLKTWDURSZJZCMILWFTALVUHVZRDLDEYIXQ

There were fifty-three letters in the message David had written to her, on the label carefully affixed to the original disk:

Dear Ada. A puzzle for you. With my love, your father, David Sibelius
.

So there it was, at last: the one-time pad that Hayato had guessed might exist. Without the original disk, without the label stuck to it, the copies they had all been working from were meaningless. The encryption, without its key, was an orphan.

From there, it took them ten minutes to decrypt the rest. Gregory's eggs arrived. He let them go cold.

“Everything okay?” asked the puzzled waitress, but they barely looked up.

They assigned each letter in the encryption its logical number—4 for
D
, 8 for
H
, 1 for
A
, 18 for
R
, 19 for
S
, 14 for
N
—and from each subtracted the numerical substitute for the letters in the message on the label: 4 for
D
, 5 for
E
, 1 for
A
, 18 for
R
, 1 for
A
, 4 for
D
.

4 minus 4 was 0.

8 minus 5 was 3.

1 minus 1 was 0.

18 minus 18 was 0.

19 minus 1 was 18.

14 minus 4 was 10.

0
,
3
,
0
,
0
,
18
,
10
translated to nothing obvious at first: it looked something like
_ C _ _ R J
.

“Try shifting every letter up to the next one,” said Ada. And
_C_ _ R J
suddenly became
ADAASK
.

They continued to work until, at last, the whole decrypted message sat before them on the screen, unpunctuated and abrupt, a telegraph message sent to them from twenty-six years in the past.

ADA ASK ELIXIR WHO IS HAROLD WITH LOVE YOUR FATHER HAROLD CANADY

It was easy to reach Frank Halbert, now the head of the old laboratory at the Bit. His information was public, and they found it quickly online. He answered Ada's e-mail immediately. Yes, he said; the program's still running.

1980s

Boston

L
iston was waiting for her in the hallway outside David's room at St. Andrew's. Ada kept one hand in her jacket pocket, around the four-leaf clover charm she had taken out of David's grip. Would he miss it, when he woke? Inside it, the key rattled gently.

When they reached Savin Hill, Ada said there was something she needed from inside David's house, and Liston, kindly, left her alone. She entered through the kitchen, walked into David's office. And then she moved directly to the filing cabinet that she had tried in vain to open the first time she ever searched the house.

The tall tan cabinet still had its crooked look from when she had tried to force it open with a crowbar. Now, holding her breath, she fitted the silver key neatly into the lock. It turned.

She paused before pulling open the top drawer. She was relieved to find it empty.

The second drawer, however, was nearly full to the brim with a stack of pages printed on a dot-matrix printer, every page still connected to its neighbor, every perforated edge still attached. She lifted the stack out of the drawer.

The Unseen World
, the first page said, in larger font across the top. She paused: it was the same title David had given to the document that Gregory had found on his computer, which she had not yet made sense of.

Below it: pages and pages of code. A hundred printed pages. Maybe more. It was written in an iteration of Lisp, and it looked like a game; she could see that; she recognized its cues and commands, its particular shape. As for what it was meant to do: that was beyond her. And she did not know on what platform it could be run.

Was this, she wondered, what David had been working on, secretly, in his final years in the house? All those evenings he had disappeared into his office; all those mornings she had woken him up after he had fallen asleep, the night before, at his desk?

She reassembled the pages. She placed them on his desk, and then turned on his computer.

Already she had been through every file he'd saved, and she had seen nothing like this document. Still, she searched again, and then once more, looking for anything that resembled
The Unseen World
in electronic form.

She found nothing.

She'd have to manually type every line of the printed text herself, then—slowly and painstakingly, avoiding mistakes that might corrupt the program. Only once she had an electronic copy could she begin to determine the platform it required.

That evening, she began.

(define

flip

#decl (process)

(cond ((type? , rep subr fsubr)

(set read-table (put (ivector 3444 0) (chtype (ascii i \() fix) i \))

(evaltype form segment)

(applytype grrt fix)

(put (alltypes) 3 (4 (alltypes)))

(substitute 2 1)

(off .bh))))

(indec (ff) string)

(define ilo (body type np1 np2 “optional” m1 m2)

#indec ((body np1 np2 p1 p2) string (type) fix)

(cond ((or (and (member “(open drawer)” .body)

(not (member ,nbup ,winners)))

(and (member .np1 ,winners)))

(member ,ff .body)))

(eval (parse .body)))))

(dismiss t))

\

; “subtitle kitchen, shawmut way”

(define house ()

(cond ((verb? “search”)

(say)

2009

Boston

T
here was a seat available on the same plane to Boston that Gregory was taking. It was leaving the next day.

After meeting with Gregory, Ada didn't go back to Tri-Tech. She couldn't. She would find out from Tom, who would find out from Bill, how the meeting had gone. She would call in the next day and tell Bill that she had to go to Boston. “Family emergency,” she would say—and, because he had never once asked her anything about her life, because he had no sense that, in fact, she had no family, he wouldn't know any different. In a way, she told herself, it was true.

She would quit, she decided. She had to. But all of that could wait until her return.

That night, at home, she turned in a full circle, assessing what to pack. She couldn't think well. She mouthed the names of items as she put them into her suitcase. It was winter. January. That year, San Francisco was cold, but Boston would be freezing. She opened the bottom drawer of her dresser, rifled through the clothing in her closet. Since moving to the West Coast, she had shed most of her cold-weather gear. She remembered Boston's version of winter as something breathtaking, unkind.

She was certain she was forgetting something. At 6:45 the following morning, she left for the airport anyway, in a taxi whose driver
sang along lowly to the songs on the radio. She would meet Gregory there.

On the plane, in a seat seventeen rows behind Gregory's, Ada was apprehensive. Boston existed for her as an alternate universe, a place that she had left behind too young to have an adult comprehension of it, a place constructed mainly out of her memories of the people she had known there. Too many of them, now, were gone.

She had booked a room in a hotel downtown, a decent place that belonged to the same chain she chose in any city she was sent to for work. Gregory hadn't invited her to stay on Shawmut Way. “Too weird with Kathryn,” he said, by way of explanation. “She drops by sometimes to get stuff.” They said goodbye at Logan. They would meet the next morning at 9:00, at Frank Halbert's lab at the Bit.

The next day, she put on her warmest clothes. Boston had shocked her: it had been eighteen degrees outside when she landed, and a bitter wind made the city feel colder. She remembered David as he had marched her around the Fens, even in January: “Put on your scarf, my dear,” he had said, and off they had gone. Once or twice they had spotted small birds, improbably, and David had yelped with enthusiasm, and named them, and spoken their Latin names, too.

At 8:30, she walked outside into the bracing air and headed toward the Bit. She knew where she was going without having to consult any person or device. Someplace in her memory, she thought, a map of the city had lain dormant for twenty years.

F
rank Halbert looked very much the same. Ada was relieved to find this: she had not seen him since Liston's funeral; and although that had been only five years before, she somehow expected to find everything, and everyone, changed. In fact, Frank looked in some ways better than ever. He was handsome still, gray-haired and upright; in recent years he had gained a gravitas he lacked earlier in his career. Ada could remember him at twenty-eight or so, when he had been the youngest member of the lab; when David had spoken of him fondly but somewhat dismissively. It had been an underestimation of him, Ada thought.

“How extremely nice to see you,” Frank said warmly. And he shook each of their hands with both of his.

The Steiner Lab, on the other hand, was entirely different. Every member of the original group but Frank had retired: first Liston, before her death; and then Charles-Robert, to the North Shore; and then Hayato, to Arizona. The physical space of the lab, too, had moved into the building next door; it had grown in size and in prestige, and accordingly had been granted a more prominent site for its work.

Young people—grad students, Ada thought—glanced at them as they passed. She wondered if any of them had heard of David Sibelius, if any of them knew the history of the lab. Probably not, she figured. Probably David had been erased from the official history of
the lab, an embarrassing chapter that went undisclosed in the literature and undiscussed with donors. Too many questions about his background to include him as a prominent part of their institutional history. Despite Liston's efforts to credit him with some of the lab's most important accomplishments, the Bit itself refused to, in any official capacity.

“This way,” said Frank, leading them down a brief hallway and into his large and light-filled office. Ada noticed it immediately: there, in a framed picture on the wall, was the Steiner Lab she remembered from her youth. It had been taken in the fall, and the six of them were standing just outside the lab's old building, next to a tree with changing leaves. There was Liston, wearing her knitted Red Sox hat, Charles-Robert, Hayato, Frank—all wearing the fashions of the late 1970s—and there, surprisingly, was David, the tallest of all of them, standing upright in the center, his hands in the pockets of his wool jacket, a thick scarf around his neck, his large familiar glasses resting on the bridge of his nose. It was the only unofficial photograph Ada had ever seen of him. He was grinning broadly, about to laugh. And there, standing slightly behind him, was Ada, eight or nine years old, dressed in a green coat and yellow corduroy pants, hopelessly unfashionable, completely unaware. Happy.

“How did you get him to be in this?” asked Ada.

“He lost a bet, I think,” said Frank, smiling.

They sat, three in a row, while Frank opened his laptop.

He pulled up a simple interface, not much different than the program from the 1980s that Ada remembered.

Hello
, he typed. And the program responded:
Hello
.

Ada did not expect ELIXIR to have evolved very much. In fact, she had been surprised when Frank had told her it was still running. Liston had always tried to keep her up to date with the work of the lab, and by the late 1980s, Ada knew they had begun to shift their focus
to other projects. There was a sort of general falling-out-of-fashion, in the second half of the 1980s, of AI language processing as a field of study. Creating a generalist chatbot was no longer perceived as a highly useful direction for computing; instead, researchers began to focus their efforts on creating systems for specific purposes. ELIXIR was too ambitious—some might say too impractical—a gimmick for hobbyists or science fiction enthusiasts, not for serious computer scientists.

Later, in 1990, the establishment of the Loebner Prize, funded by a private donor, awarded each year to the team who developed the program that came closest to passing the Turing Test, seemed to confirm the idea that respected institutions were no longer footing the bill for the development of programs like ELIXIR—programs designed to acquire human language simply to see whether it could be done. The Loebner Prize was the soapbox derby of the computing world: something that an amateur or hobbyist might participate in because of his or her own enjoyment of the process. Nothing to be taken too seriously.

She was almost glad that David was gone before he could see the Steiner Lab, helmed by Liston, turn its attention to other pursuits: in the late 1980s, the development of a programming language that fell quickly into and out of use; in the 1990s, a sort of self-organizing networking protocol. Until the very end of his coherence, David sometimes asked after ELIXIR, which was a word that faded slowly from his memory, even after words like
tree
and
food
were lost—even after
Ada
,
daughter
,
computer
. Even after
David
.

“Actually, Ada,” said Frank, “why don't you take over?”