Foundation’s Friends

“No action, Bronwen.”

“If you had received such an order from it, would you have obeyed?”

“Not without checking that the order had originated from a human being, or obtaining the approval of a human being. “

“So we haven’t proved anything. “ There was no response to this; Chile had no reason to interpret the remark as a question to him, and the human beings recognized its rhetorical nature. An uncomfortable silence ensued.

“Bronwen, let me try something?” Ling finally spoke, in doubtful tones. The commander nodded, not bothering to ask the nature of his idea.,

“Chile, the robot replaced that cube as nearly as possible to the place it was before the cliff broke off. It seems concerned with it. Without going to extremes if it interferes, approach the cube yourself as though you intended to pick it up again, and tell us how it-the robot-responds.”

There was another pause, while six people tried to imagine what was happening twenty kilometers away.

“It has interposed itself between me and the cube, and has been moving to stay so wherever I go.”

“Any body contact?”

“No. You said not to go to extremes. Shall I push it out of my way?” Ling looked thoughtfully first at Bronwen and then the others. The commander’s eyes also met theirs, in turn. Finally she nodded again.

“All right, Chile. No real force, just a suggestive shove.”

“Understood, Bronwen.” Imaginations fired up again.

“The response has been complex. It braced itself to resist my push, after I had made contact; naturally, it had to yield some distance to accomplish this. While it was setting its feet, it emitted a brief, very detailed burst of infrared, of the same general nature as we detected originally from the small cubes. This was immediately followed by a similar signal from elsewhere. It then ceased pushing against me and simultaneously seized my arm and pulled. This sent me over the cliff edge. I am now falling, and will be unable to do anything effective for the next fifty-five seconds.”

Ling blinked, and a grin spread over his face.

“Chile, did you determine the source of that other signal?”

“Direction, not distance. I did not move enough for parallax while it lasted. However, its line touches ground just at the edge of Big Drop, in Block Twenty-five, seventy-one meters from the boundary between that one and Block Thirty-seven.”

“Great. Head for that spot as soon as you’re down. We’ll meet you there.”

“All right, Rob. You no longer want me to keep track of the other robot.” It was not a question.

“Don’t worry. It’ll be keeping track of you, I expect.”

“I see.” So did the others, and there was a general rush to get into armor. There was some delay, however, in going outside.

“Hold it,” Bronwen said firmly before helmets were do

“How close?” asked Mike.

“Fifty meters for the Gold team, twenty for the rest of us. If anyone but Chile has to get near the edge, Rob’s the best anchor, so Sheila can do it. Fifty meters will give him more room to catch the surface, and us more time to help, if she does go over; twenty is enough for us. I’ll carry the rest of the reel just in case.”

“It won’t reach five percent of the way down that cliff!”

“It would take a couple of minutes to fall five percent of the way. We’ll take the chain.”

Her husband nodded. Sheila had paled a trifle, but said nothing. It was true that Ling was the heaviest of the crew, while she herself was lightest except for Chispa. She had no intention of going nearer the edge than necessary, and certainly none of going over, but Bronwen was right to be foresighted.

The chain links were carbon-filament composite a millimeter thick, preformed in jointless loops half a centimeter long and already interlocked. Neither rope nor cable was practical; no known fiber, organic, metallic, or mineral, would remain flexible at Miranda’s temperature. The link material had a tensile strength of eight hundred kilograms as straight rod under Earth conditions, dropping to about five hundred at seventy Kelvins, with some remaining doubts about its elasticity in that range and more about the nontensile stresses and possible shock brittleness in its looped shape. No one had wanted to make the field test, but an armored person weighed only about two kilograms.

They did not actually link up until a couple of kilometers from the cliff, in the interest of fast travel; but the robots, of course, were there first in spite of the much greater distance they had had to travel. There was no trouble, this time, spotting the goal.

It too was cubical in shape, but twice as tall as most of the explorers. Like the one at Barco, it was projecting a little over the edge, though not by nearly as large a fraction of its size. It was not obvious whether it was merely resting on the surface or, like the other, set in. The ground was lighter in color here, but at the moment not even Ling was paying attention to mineralogy. In fact, the group only glanced briefly at the big cube; everyone’s attention was on the two robots.

These were not standing still waiting, as had been tacitly expected. They were moving around, now slowly, now more rapidly, usually in the very short steps which went with their nearly upright carriage but sometimes leaping straight up for a distance ranging from two or three centimeters to as much as ten °meters, sometimes waving arms or kicking. There was no obvious regularity; if they were dancing, which was the first thought to cross most of the human minds, there seemed to be no tune. For a few seconds after stopping fifty meters away, the six people simply watched in silence, trying to make sense out of the phenomenon. Then Bronwen recovered her practical sense.

“Chile, report. What’s going on?”

ZH50’s answer came at once without causing visible change in his behavior.

“The robot is now exchanging continuous infrared signals with this cube, details of its signals changing as I perform various actions, while its own actions seem to correspond to signals from the cube. I am trying to ascertain the detailed relationship. “

“You mean you’re learning its language?”

“The analogy is weak; there seem no abstractions involved, and I doubt that I could work them out if there were-at least, not by myself. Co

“You mean the cube may be a pure, dedicated data processor like Dumbo, telling the robot what to check but not controlling its detailed limb actions, for example.”

“A much better analogy. It is the one which occurred to me.”

“Where is its Sheila?”

“I have no basis for a guess.”

“How long has this been going on?”

“Since I left Barco. At my first leap in this direction, there was a signal burst from the robot; then it leaped from the cliff top after me.” Ling’s nod and grin were invisible inside his helmet, but his Gold partner could imagine them.

“Had the robot received a signal before following you?” asked Chispa.

“I could not tell; the cube was below my horizon.”

“But whenever you’ve been in a position to receive, such a signal preceded its action. “

“Yes. The best example came about two thirds of the way here, when I happened to be at the top of a jump. A very complex emission from the cube was followed by the robot’s ceasing temporarily to stay with me. It disappeared briefly to the right of our path, and came back carrying one of the very small cubes. It intercepted me at one of my landing points, and extended the object to me. I took it. It then took it back and placed it on top of its own head, removed it, and handed it to me again. I imitated that gesture also. The cube adhered, but not strongly; I found I could easily remove it, and decided to leave it in place.” The human beings had not noticed the minor addition to Chile’s outline, but could see it easily enough now.

“Why didn’t you-” Bronwen cut off her question; it was plain enough why Chile hadn’t reported the incident. He had been told to observe and analyze, with the implication that reporting should wait until the group had met at Big Drop.

“Have you been able to detect anything from the cube since it has been on your head?”

“Yes. It has emitted simple signals every time I move or change attitude. It is reporting my position, very precisely, to the large cube; that has been easy to work out.”

“Sure!” exclaimed Ling. “That’s what they’re all doing. It’s a sensor network analyzing topographic changes on all this part of Miranda-maybe the whole satellite. Just what we’d do if we had the gear. Someone is checking whether the surface patterns of this iceberg which have been bothering people since Voyager really represent separate fragments of a shattered body which fell back together, or internal movements, or what. The middle-sized cube on Barco is just a relay station; this one is the equivalent of Dumbo, tying all the measures together. When we learn to read its output-Keep at it, Chile!”

“I hope that’s not merely the equivalent of Chispa’s naming a cliff for a ship, or all of us calling a range of hills a dinosaur, or someone’s describing a constellation as a goat or a long-tailed bear,” Sheila responded. “We do like to fit things into patterns, don’t we, Rob?”

“Don’t be so objective. Just because I saw your face in a Rorschach blot when we were being tested for this trip, and the whole world found out about it because the tech couldn’t control her giggles, doesn’t mean-”

“Of course not,” Bronwen cut in. The blot story was not news to Dibrofiad’s perso

“I haven’t tried that yet. I have been working on much more direct and simple signal-action correspondence. “

Ling didn’t stop to check with the commander. “Hold up for a moment and give me that cube, then go on with your tests. I’d like to see if it gives the robot any special instructions when I get close to the center.”

“The robot can see you whether you’re wearing the cube or not, and I’m the one who’s supposed to go near the edge if necessary. I’m less likely to break a piece of it off, after all,” Sheila pointed out.