Clearly a sequential chronological run-through was impractical, in more ways than one. What would be preferable was some kind of simultaneous flushing of the system, strengthening the entire network without consciously remembering every component of it. Whether such a flushing was electrochemically possible was unclear; and what such a flushing might feel like was impossible to imagine. But if one were to electrically stimulate the perforant pathway to the hippocampus, and get a great deal of adenosine tri-phosphate past the blood-brain barrier, for instance, thus stimulating the long-term potentiation that aided learning in the first place; and then impose a brain-wave pattern stimulating and supporting the quantum oscillations of the microtubules; and then direct one’s consciousness to review the memories that felt most important to one, while the rest were being reinforced as well, unconsciously…

He ran through another accelerando of thought on this issue, then crashed blank on it. There he was, sitting in his apartment living room, blanked, cursing himself for not at least trying to mutter something into his AI. It seemed that he had been onto something — something about ATP, or was it LTP? Well. If it was a genuinely useful thought, it would come back. He had to believe that. It seemed probable.

As it did, more and more as he studied the issues, that the shock of Maya’s amnesiac moment had somehow propelled Michel into the quick decline. Not that such an explanation could ever be proved, or that it even really mattered. But Michel would not have wanted to survive either his memory or hers; he had loved her as his life project, his definition of himself. The shock of Maya blanking on something so basic, so important (like the key to memory restoration)… And the mind-body connection was so strong — so strong that the distinction itself was probably false, a vestige of Cartesian metaphysics or earlier religious views of the soul. Mind was one’s body’s life. Memory was mind. And so, by a simple transitive equation, memory equaled life. So that with memory gone, life was gone. So Michel must have felt, in that final traumatic half hour, as his self tumbled into a fatal arrhythmia, under the anguish of grieving for his love’s death-of-mind.

They had to remember to be truly alive. And so ecphorization, if he could figure out the appropriate anamnestic methodology, was going to have to be tried.

Of course it might be dangerous. If he did manage to work up a memory reinforcer, it would flush the system all at once, perhaps, and no one could predict what that would feel like subjectively. One would just have to try it. It would be an experiment. Self-experimentation. Well, it wouldn’t be the first time. Vlad had given himself the first geronto-logical treatment, though it could have killed him; Jennings had inoculated himself with live smallpox vaccine; Arkady’s ancestor Alexander Bogdanov had exchanged his blood for that of a young man suffering from malaria and tuberculosis, and had died while the young man had lived for thirty more years. And of course there was the story of the young physicists at Los Alamos, who had set off the first nuclear explosion wondering among themselves whether it might not burn up the entire atmosphere of the Earth, a somewhat disturbing case of self-experimentation, one had to admit. Compared to that ingesting a few amino acids seemed no very great thing, something more like Dr. Hoffman trying LSD on himself. Presumably ecphorizing would be less disorienting than an LSD experience, for if all one’s memories were being reinforced at once, consciousness would surely not be capable of being aware of it. The so-called stream of consciousness was fairly unilinear, it seemed to Sax on introspection. So that at most one might experience a quick associative train of recollections, or a random jumble — not unlike Sax’s everyday mentation, to tell the truth. He could handle that. And he was willing to risk something more traumatic, if that was what it happened to take. He flew to Acheron.

Up at Acheron a new crowdwas in place in the old labs, now vastly expanded, so that the entire high long fin of rock was excavated and occupied — it was a city now of some 200,000 people. At the same time it was still, of course, a spectacular fin of rock some fifteen kilometers long and six hundred meters high, while never more than a kilometer wide at any point; and it was still a lab, or a complex of labs, in a way that Echus Overlook had long since ceased to be — something more like Da Vinci, with a similar organization. After Praxis had renovated the infrastructure, Vlad and Ursula and Marina had led the formation of a new biological research station; now Vlad was dead, but Acheron had a life of its own, and did not seem to miss him. Ursula and Marina directed their own little labs, and lived still in the quarters they had shared with Vlad, just under the crest of the fin — a partially walled arboreal slot, very windy. They were as private as ever, withdrawn into their own world even more than they had been with Vlad; and they were certainly taken for granted in Acheron, treated by the younger scientists as local grandmothers or great-aunts, or simply as colleagues in the labs.

Sax, however, the younger scientists stared at, looking just as nonplussed as if they were being introduced to Archimedes. It was as disconcerting to be treated in such a way as it was to meet such an anachronism, and Sax struggled through several conversations of surpassing awkwardness as he tried to convince everyone that he did not know the magic secret of life, that he used words to stand for the same things as they did, that his mind was not yet altogether shattered by age, etc.

But this estrangement could also be an advantage. Young scientists as a class tended to be naive empiricists, also idealistic energetic enthusiasts. So coming in from outside, both new and old at once, Sax was able to impress them in the seminars Ursula convened to discuss the current state of memory work. Sax laid out his hypotheses concerning the creation of a possible anamnestic, with suggestions for various lines of experimental work on these possibilities, and he could see that his suggestions had for the young scientists a kind of prophetic power, even (or perhaps especially) when they were quite general comments. If these vague suggestions happened to chime with some avenue these people were already exploring, then the response could be enthusiastic in the extreme. In fact it was a case of the more gnomic the better; which was not very scientific, but there it was.

As he watched them Sax realized for the first time that the versatile, responsive, highly focused nature of science that he was getting used to in Da Vinci was not confined to Da Vinci alone, but was a feature of all the labs arranged as cooperative ventures; it was the nature of Martian science more generally. With the scientists in control of their own work, to a degree never seen in his youth on Earth, the work itself had an unprecedented rapidity and power. In his day the resources necessary to do the work would have belonged to other people, to institutions with their own interests and bureaucracies, creating a ponderous and often foolish clumsy scattering of effort; and even the coherent efforts were often devoted to trivial things, to the monetary profits of the institution in control of the lab. Here, on the other hand, Acheron was a semiautonomous self-contained community, answerable to the environmental courts and to the constitution of course, but to no one else. They chose among themselves what to work on, and when they were asked for help, if they were interested, they could respond immediately.

So he was not going to have to do all the work of developing a memory reinforcer himself, not by any means; the Acheron labs were highly interested, and Marina remained active in the city’s lab of labs, and the city still had a close relationship with Praxis, with all its resources. And many labs there were already investigating memory. It was a big part of the longevity project now, for obvious reasons. Marina said that some twenty percent of all human effort was now being devoted, in one form or another, to the longevity project. And longevity itself was pointless without memory lasting as long as the rest of the system. So it made sense for a complex like Acheron to focus on it.