David Weber - Ashes of Victory

"And the arm?"

"That's going to be both easier and harder than the face. The good news is that, despite the primitive facilities he had, Fritz did a really good job when he took it off."

Allison nodded, but her serene expression didn't fool Honor. It couldn't have fooled anyone who could taste her jagged emotional response, even now, to the thought of her daughter, lying more than half-starved and wounded almost to death, while a doctor worked with frantic haste to amputate the shattered ruin of her arm with nothing but an assault shuttle's emergency med kit for equipment and supplies.

"He took particular care with the nerves," Honor went on, her voice as serene as her mother's face, "and Daddy says we shouldn't have any trouble at all with the interfaces there. As I say, that's the good news. The bad news is that, unlike the face and the eye, I'm going to have to start from scratch with the arm."

Allison nodded once more, this time with a grimace of sympathy. Despite the best the technical types could do, an artificial limb remained just that: artificial. The designers could do many things with their prostheses, but not even the Solarian League's medical establishment could make one which obeyed exactly the same nervous impulses, and in exactly the same way, as the natural limb it replaced had obeyed. There were too many idiosyncratic differences from individual to individual. It would have been possible to chart the unique impulses whoever was to replace the limb had used, after which modifying the software to obey them would have been fairly simple and straightforward. But doing that would have taken months and required the recipient to put her missing natural arm—and hand, and fingers—through every aspect of their full range of movement for the sensors recording the neural commands. In practical terms, it made more sense to build the limb with a software package that emphasized heuristic functions that learned from doing and then simply let the recipient (and the software) learn to use it. Even then, however, a certain sense of the alien or the once-removed about the new limb would always remain, however well she learned to control it, which was the real reason such prostheses weren't simple "plug and play" devices.

Honor had learned to adjust for the fact that the artificial nerves in her face simply did not report sensory data the same way live ones did. At the moment, she felt nothing at all on her left cheek. Had her implants been working properly, however, she would have "felt" the pressure of the growing sea breeze quite differently on the two sides of her face... and even after so many years, the sensations from the left side would have felt artificial. Which was fair enough, since that was precisely what they would have been. She sometimes wondered if it would have been easier to adjust if they'd had to replace the nerves in both cheeks, but she had no intention of experimenting to find out.

That artificiality was the main reason so many star nations, including the Star Kingdom, had no extensive market in bio enhancement. Some nations did, of course. The rogue bio-modifiers of Mesa came to mind almost automatically, but her mother's native Beowulf had also supported a lucrative enhancement market. In one way, Honor could understand the temptation, for there had been features to the eye the Peeps had burned out that she missed sorely, like the low-light vision and telescopic and microscopic functions. But even there, what she saw had never seemed quite as alive—as "real"—as what the unenhanced vision of her right eye had reported. It was something that probably could never be fully described to anyone who hadn't experienced it directly. For that matter, she supposed it might well be purely psychological, although it was reported with near total unanimity by everyone who'd received similar implants. The closest she'd ever been able to come to defining the difference even for herself was to think of what she saw through her left eye as a very, very good, three-dimensional flat screen presentation. Again, she'd often wondered whether or not replacing both eyes, so that she no longer had the "distraction" of her natural eye's input, would have ameliorated the problem in time. And, again, she had no intention of ever finding out.

But there were people who'd made the opposite choice. Indeed, in some of humanity's far-flung cultures, like Sharpton, where the cyborg was a sort of cultural icon, it was as routine for an individual to replace limbs and eyes with artificial improvements as it was for someone on Manticore to have her teeth cleaned and straightened. Or her ears pierced, for that matter. Personally, Honor couldn't imagine doing such a thing. In fact, the very thought made her uncomfortable—probably because she'd spent so much of her life in space. After so many years in an artificial exterior environment, she felt no temptation whatsoever to turn her own body into an artificial interior environment, whatever advantages over mere flesh and blood it might have brought with it.

Although the Star Kingdom didn't practice that sort of casual enhancement, it wasn't out of any horror of "cyborgian monstrosities." Honor had met a few people, mostly from places in the Solarian League, whose enhancement had been so obvious and extreme as to make her feel actively ill at ease, but those were exceptions. Most people who had themselves enhanced went to some lengths to make the enhancements appear as much like natural (albeit as perfectly developed natural) limbs, as possible, and the same held true for the minority of people who couldn't regenerate.

She had no qualms over how her new arm would look or feel to anyone else, and she and her father had visited the firm which would build it to discuss the enhanced features they wanted, since if she had to have a prosthesis, it would have been stupid not to build in as many advantages as she could. The techs who would produce it had been given access to her BuMed records, and she felt confident that, externally, they would reproduce her original arm perfectly, right down to the small mole on the inside of her left elbow. The synthetic skin covering it would have precisely the right texture and coloration. It would even tan or sunburn exactly as her natural skin, and it would maintain exactly the same skin temperature as her right arm did.

Internally, it would be far stronger and tougher than the limb it replaced, and she'd thought of several other small features she wanted incorporated into it, while her father had suggested a couple that hadn't occurred to her on her own. But marvelous as it would be, it would also be a totally inert, dead lump hanging from the stump of her natural arm, initially, at least. She would have to learn to use it all over again, from scratch, the way an infant learned to use her arms. Worse, she would have to unlearn the way her natural arm had once worked, because none of the old nerve impulses or commands would evoke precisely the same responses they once had.

She'd never had to do that with her facial nerves. There, it had been a simple matter of learning to interpret new passive data and match it with old information files. And even with her eye, there'd been relatively few new control functions to learn, for the muscles of her eye socket had been untouched by the damage to the eye itself. They'd moved the new eye precisely as they had the old, and focusing and automatic adjustment for natural light conditions had been built into the software. All she'd really had to learn was a pattern of specific muscle contractions which activated or deactivated any of the special functions she wanted to use.

But it wouldn't work that way for the arm, and she was honest enough to admit that she felt a certain dread whenever she thought of what this therapy was going to be like. And the fact that she'd spent so many years training in coup de vitesse was only going to make it still worse, because she'd spent so much time programming muscle-memory responses into herself, and every one of them would have to be deleted and reprogrammed. She would probably be able to retrain herself with the prosthetic well enough to fool most people into believing she'd fully mastered it within no more than nine or ten T-months, but it would take years of hard, unremitting work to completely reintegrate her control of it. For that matter, she never would have quite the same degree of fine motor control she'd once had.