by Hal Clement
“You’ve got your feet on the wrong pedestal, dear. If we’re trying to give it orders at all, the assumption is that it can understand us, and must be human made.” His wife didn’t dwell on the point, but went on. “We have to try, anyway.” She didn’t bother to check for open channels; there was always one through to the robot. “Chile.”
“Yes, Bronwen.”
“Any change?”
“None. It is standing facing me, presumably waiting for me to do something. It has now cooled down to ambient temperature; I would say that any doubt about its being a robot is gone.”
“You can’t sense an atomic power source?”
“I am not equipped to pick up such radiation directly.”
Bronwen had known that, but was feeling desperate.
“Try talking to it directly—”
“I have done so, every way I can.”
“This time, send your message as an order to approach you. If it responds, order it to follow you back to Dibrofiad. “ There was a brief pause.
“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 donned. “We’re going to the Big Drop, and no one could stand a twenty-kilo fall; it would be about four hundred and fifty meters on Earth. I still don’t trust the chains, but we link up this time.”
“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. Connected with Dumbo, the chances would be better. It appears that the robot is reporting to the cube, and receiving general instructions for action from the latter.”
“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 le
ft 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 personnel. “Your hypothesis is sensible, and we can keep on testing it. Chile, has this robot objected to your approaching the big cube?”
“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.
“We don’t need to worry about the cliff strength here. Would they have put this big gadget where it is without checking? Never mind the cube, Chile, but I’m going to find out—”
Bronwen was somewhat dubious, but said nothing. If Rob did cause the other robot to break off the language lesson, it would at least give some idea of the unit’s concerns and priorities. Only when the man took an unusually long step toward the cube did she utter a caution.
“It’s a long way down, Rob. I said that Sheila would be first if anyone had to go near the edge. You get set to anchor.”
Ling checked himself, a humorous sight under the local gravity and traction. “I’ll head for the right side, Sheila for the left. If one goes over, the cube will catch the chain and be a real anchorage.”
“All right. But don’t get casual.”
“I won’t. Keep an eye on Chile’s friend. I expect it’ll do something, considering how it reacted back at Barco when he tried to get the cube there.”
The whole group eased closer to the edge, Orange to the left, Green to the right, men leading by a few meters, safety chains slack.
Rob was quite right in principle, but hadn’t foreseen the detail. As he approached the right side of the block, gathering in the free chain as Sheila neared the other, the language lesson was indeed interrupted. Casually using Chile as a kick-off mass, the ghost dived straight for the man, and just as casually used his inertia to keep itself from going past the edge. The push sent Ling over, naturally, since his mass was much less than the robot’s.
The chain did not catch on the presumed data unit, for the block lifted itself smoothly a meter and a half to let the line pass underneath as Rob’s new momentum pulled it straight.
Quick planning was easy, quick execution impossible. Sheila was standing almost erect, and even though the footing was rough, could not at once leap horizontally; she had to fall to a steep angle in the desired direction first, and this had to take over a second. Pulling up her feet would be no help; she would merely fall straight and surrender what little traction she had without getting the needed tilt.
The other two teams had the same problem. Chispa and Bronwen also started down so that all four limbs could search for traction; their partners, about the same distance from the edge but closer to it than the women, leaped toward each other.
By the time they met, Chile was still helplessly drifting from the push he had received, Ling was starting to disappear below the edge, and Sheila was ready to jump away from it and him. He had released the slack in the chain connecting them.
“Hit us, Sheil’ !” called Mike. She needed no instruction. A little toe work in the surface cracks headed her toward the two-man system slowly spinning and drifting edgeward as it settled toward the ground. She had bent her knees a little as she went down, and now straightened them firmly.
By the time she reached her target and complicated the system, it was on the ground. Ling was nearly out of sight, and Chile, who had had no control over his original spin, had only partly stopped his flight with his hands and was on the first bounce.
“We’ve got you, and the girls have us. There’s plenty of traction. Start hauling in!” Mike snapped. “Not too hard!”
She pulled quickly anyway. The sooner the slack was taken up and she could start doing something useful, the better. By the time she felt resistance, the falling man was out of sight, one could only estimate how far. She abandoned responsibility for her own safety to the others, and drew steadily, hand over hand, gripping the fine chain as effectively as she could with her insulated gloves. She barely noticed that the big cube had settled back where it had been. From her position, the other robot was hidden beyond it; for the moment, its possible activities didn’t concern her.
“Rob, are you all right?” she called.
“Sure. Swinging in toward the cliff now. I take it you’re anchored all right—if you come over too, it could be awkward.”
“I’m solid. Don’t look down.”
“Oh, it’s not that bad. There’s no haze to suggest distance; my head knows it’s twenty kilos, but my stomach isn’t sure it’s down. I’m about to hit the cliff; stop pulling up for a moment so I can catch it. It’s pretty rough, and I may be able to hang on myself.” There was a pause, and Sheila braced herself for a possible jolt along the chain, but felt nothing. “Missed the hold. I bounced, but only a little. I ought to get it next time. It’s not quite vertical, I think; maybe I can walk up it, with the rope helping. Here I come.” There was a pause. �
��Yep, it’s not straight up and down; I’m hanging against the rock. You can pull again. So much for the strength of this cliff.”
“What? Is it cracking?” Chispa was first with the question, by a split second.
“Oh, no, but if that data unit can fly, our logic was a bit shaky. Just don’t stamp, please, until I get back up. More to the point, what’s that other robot doing now?”
Chispa, who could see farthest around the right side of the cube, replied, “Nothing. It’s just standing there. Why?”
“Well, if you didn’t happen to see, I think it pushed me over; and I was wondering if it had shown the same feeling about anyone else.”
“Chile! Keep close to that thing and make sure it doesn’t do a repeat!” snapped Bronwen.
“Shouldn’t I be helping bring Robert up? His danger seems more immediate.”
“We can get him. If he’s right—I couldn’t see him on that side of the block—the other danger is greater.”
“I understand.”
“Talk to it, if you’ve reached that level, and ask why it did it,” suggested Ling.
“We have not reached that level of abstraction.”
“At least we’ve learned one thing; this stuff is alien,” Rob resumed, very calmly all things considered. “No robot made on Earth could have done that to what it recognized as a human being. We don’t have First Law protection from it. Maybe we don’t have any kind; maybe whoever made it doesn’t use the Three Laws in their design.”
Chile had stopped at last, and was “walking” back toward the scene of action. “Such a positronic brain is not possible,” he said flatly. “I will try to find human identifying signals, if any exist, in its communication with the data processor, but I expect they will be too abstract for my present intuition base. Is Robert nearly up?”
“Nearly.” Ling and Sheila spoke almost together. No one suggested aloud that the ghost’s brain might not be positronic. “There can’t be much of this chain still out,” the woman added.
“The robot is getting between me and the cube again,” Chile reported quietly. “I will go to the left side, so I can help with Robert’s chain. I am still monitoring signals. I can’t get very close, of course, without using force on the robot. I assume that is not yet the policy.”
