“Conrad! Are you-?” Yanderman began.
“Listen!” Conrad exclaimed. “I have it now, but we’ve got to be quick.” He was scrambling up from the bed, twisting into a kneeling position facing them. “Do you hear me? I know what’s wrong and I know what has to be done! Maxall, you have to cut the power off-I mean … Well, stop it getting to the cortex but not completely, just hold it down to a sort of trickle and-”
He stopped, aware that he wasn’t making sense to his listeners. A bead of sweat ran down his face like an insect.
“Get a grip on yourself, Conrad,” Yanderman advised, moving close in an effort at reassurance. “You’ve had some kind of a shock, and-”
“I know, I know!” Conrad clutched at his arm. “it’s because I’ve seen what’s got to be done! You were wrong about the visions people like me get-they’re not memories, they’re messages, and I’ve had a message that tells me what to do! We’ve got to cut back the power to the cortex.”
“But this is impossible!” Maxall snapped. “We depend on it-it runs everything. If we cut off its power we starve, we freeze, we’re done for.”
“But We’ve got to cut back the power. Not shut it off, just keep it low. Ohhh!” Conrad’s frantic words dissolved in a moan of desperation. “Look, is a madman crazy when he’s asleep?”
“What?” Yanderman jerked his head.
“Is a madman crazy when he’s asleep? I don’t think so. And he’s not dead, either, so it’s not killing him to make him sleep.” Conrad stared up at the low ceiling. “I almost have it all, you see, but I’m still-still arranging it. I think there’s a way of ensuring that only a trickle of power gets to the cortex, enough to keep the automatic things going like the heating and foodmaking, but not enough to-Oh, no wonder you don’t understand.” He slapped his thigh. “The most important thing is what I haven’t said.
“Look, this-this thinking machine inside the dome. It’s laid out like a human brain. There’s a level which attends to routine matters, comparable to breathing, and this never stops or goes wrong and uses only a little power. But there’s another level, responsible for big decisions, which uses all the power it can get and when the power is low is-is unconscious.
“And on this level the cortex has been hopelessly insane, with brief lucid intervals, for four hundred and sixty years, ever since it was infected with the disease against which the barrenland was created …”
XXIII
There was a stunned silence. Maxall broke it, shifting his weight with a scuffling sound as he spoke.
“How do you know? I mean-how do you think you know?”
Conrad felt an overwhelming wave of relief. He closed his eyes and leaned back against the wall of the hovel.
“I’ll try and tell you, but it’s got to be quick, because there isn’t much time. It’s sunny today and the stored power is building up rapidly. My head’s full of pictures which I scarcely understand, all jammed in together in a single instant …” He pressed his fingers hard against his forehead. In a slow, effortful voice, with many hesitations, repetitions and gropings for words, he pieced out the explanation which had come to him.
First: the nature of his visions, and Granny Jassy’s, and all others similar. They were not extraphysical recollections of the past. They were received messages, or signals.
And the burden of the message was simple: Help me!
In a time when the world was covered with cities of up to tens of millions of people, and not this world only but others, circling other stars, there had come a point at which the sheer numbers wishing to walk to other worlds-restless, bored with their long lives, hungry for the sights, sounds, sensations of alien environments-threatened to outstrip the capacity of the equipment handling the incredible traffic. The means used, in itself, was so complex it had always had to be managed at second-hand-not by individual persons, but by massive thinking machines. And the machines were inadequate.
Hence the development of the organochemic cortex: to all intents, a manufactured brain, with a personality, the gift of consciousness, all the discrimination of a human genius combined with the tireless reliability of an insensitive machine.
Such a cortex was installed at Terminal Station A, the largest centre for interstellar transport on the planet. From the three-mile dome arching above the Station it was possible to walk to any of a thousand distant worlds.
And back.
And from one such distant world somebody returned bearing in the cerebrospinal fluid of his body the virus of a disease named in the traditional lore of the Station as encephalosis dureri, which incubated and brought insanity.
No plague had ever before been transmitted on the scale of this one. Within days of the first outbreak it was on a hundred different worlds; within weeks, it had reached every planet known to mankind. As though one had emptied a bucket of sand into a precisely-tuned engine, the sophisticated complex of interstellar society ground to a halt.
Stripped of their sanity, people died-in accidents, in fires, by famine or explosion or a myriad other disasters. In the midst of primal chaos, the very few who were naturally immune stood as long as possible against the searing blast of the collapse, until they too were overwhelmed.
The ancestors of those now living at the centre of the barrenland had been a group of such natural immunes, sent to try and repair this largest of all interstellar transit points.
They started work under the impression that what had gone wrong was the simple consequence of a madman’s interference-some diseased mind among the Station’s human staff, they believed, had altered control settings or distorted the instructions given to the organochemic cortex. At that time, the cortex operated everything in the Station area: not just the actual process of transportation, but every service provided for the convenience of travellers.
The cortex knew better, and could not explain.
There was something so completely human about the despair Conrad had sensed that it had overcome him; it was as if he himself had been in the tormenting plight which the manufactured organochemic brain had endured uncounted times since the onset of the contagious madness. Which was to know that it was going insane, and to be able to do nothing about it.
The cortex was powered by the same source as the rest of the Station-the original emergency power supply, switched on to keep the cortex functioning after the disaster. When the stored power was low, as for instance after expenditure on the use of heatbeams, the cortex was practically unconscious. As the power built up again, its level of activity rose to a kind of incipient awareness. In this condition, it was sufficiently conscious to realise that when the power reached maximum the sleeping layers of its personality would arouse-and be insane because in the nutrient fluid bathing the entire artificial organism the viruses were still multiplying.
They were not like ordinary viruses. In some manner they made false connections between brain cells; the energy available at a synapse was a sort of stimulus to them. As it were, they caused innumerable short circuits and hence random patterns of response.
The effect on the cortex was to bring into operation an overload device intended primarily to limit the number of simultaneous traffic problems it was coping with. By that time it was no longer able to reason; it sought to expend energy and hurl itself into unconsciousness again for a period of recuperation.