“Now you’re treating me like a tourist guide again, and I’m not nude.”

“At that, even nudity is less frightening than Intuitionism. ... But what’s this about superstition?”

“Not really superstition, I suppose, but most of the people of the city tend to stay away from this part of the corridor-complex.”

“But why?”

“Because of what I’m going to show you.” They were walking again. “Hear it now?”

She stopped and Denison listened anxiously. He said, “You mean that small tapping sound? Tap—tap— Is that what you mean?”

She ran ahead in slow, loping strides with the slow-motion movement of the Lunarite in unhurried flight. He followed her, attempting to ape the gait.

“Here—here—”

Denison’s eye followed Selene’s eagerly pointing finger. “Good Lord,” he said. “Where’s it coming from?”

There was a drip of what was clearly water. A slow dripping, with each drip striking a small ceramic trough that led into the rock wall.

“From the rocks. We do have water on the Moon, you know. Most of it we can bake out of gypsum; enough for our purposes, since we conserve it pretty well.”

“I know. I know. I’ve never yet been able to manage one complete shower. How you people manage to stay clean I don’t know.”

“I told you. First, wet yourself. Then turn off the water and smear just a little detergent on you. You rub it— Oh, Ben, I’m not going through it yet again. And there’s nothing on the Moon to get you all that dirty anyway.... But that’s not what we’re talking about. In one or two places there are actually water deposits, usually as ice near the surface in a mountain shadow. If we locate it, it drips out. This one has been dripping since the corridor was first driven through, and that was eight years ago.”

“But why the superstition?”

“Well, obviously, water is the great material resource on which the Moon depends. We drink it, wash with it, grow our food with it, make our oxygen with it, keep everything going with it. Free water can’t help but get a lot of respect. Once this drip was discovered, plans to extend the tunnels in this direction were abandoned till it stopped. The corridor walls were even left unfinished.”

“That sounds like superstition right there.”

“Well—a kind of awe, maybe. It wasn’t expected to last for more than a few months; such drips never do. Well, after this one had passed its first anniversary, it began to seem eternal. In fact, that’s what it’s called: ‘The Eternal.’ You’ll even find it marked that way on the maps. Naturally people have come to attach importance to it; a feeling that if it stops it will mean some sort of bad fortune.”

Denison laughed.

Selene said, warmly, “No one really believes it, but everyone part-believes it. You see, it’s not really eternal and it must stop some time. As a matter of fact, the rate of drip is only about a third of what it was when it was first discovered, so that it is slowly drying. I imagine people feel that if it happened to stop when they were actually here, they would share in the bad fortune. At least, that’s the rational way of explaining their reluctance to come here.”

“I take it that you don’t believe this.”

“Whether I believe it or not isn’t the point. You see I’m quite certain that it won’t stop sharply enough for anyone to be able to take the blame. It will just drip slower and slower and slower and no one will ever be able to pinpoint the exact time when it stopped. So why worry?”

“I agree with you.”

“I do, however,” she said, making the transition smoothly, “have other worries, and I’d like to discuss them with you while we’re alone.” She spread out the blanket and sat on it, cross-legged.

“Which is why you really brought me here?” He dropped to hip and elbow, facing her.

She said, “See, you can look at me easily now. You’re getting used to me. ... And, really, there were surely times on Earth when near nudity wasn’t something to be exclaimed over.”

“Times and places,” agreed Denison, “but not since the passing of the Crisis. In my lifetime—”

“Well, on the Moon, do as the Lunarites do is a good enough guide for behavior.”

“Are you going to tell me why you really brought me here? Or shall I suspect you of planning seduction?”

“I could carry through seduction quite comfortably at home, thank you. This is different. The surface would have been best, but getting ready to go out on the surface would have attracted a great deal of attention. Coming here didn’t, and this place is the only spot in town where we can be reasonably safe from interruption.” She hesitated.

“Well?” said Denison.

“Barren is angry. Very angry, in fact.”

“I’m not surprised. I warned you he would be if you told him that I knew you were an Intuitionist. Why did you feel it so necessary to tell him?”

“Because it is difficult to keep things for long from my— companion. Probably, though, he doesn’t consider me that any longer.”

“I’m sorry.”

“Oh, it was turning sour anyway. It’s lasted long enough. What bothers me more—much more—is that he violently refuses to accept your interpretation of the Pionizer experiments you ran after the surface observations.”

“I told you the way it would be.”

“He said he had seen your results.”

“He glanced at them and grunted.”

“It’s rather disillusioning. Does everyone just believe what he wants to?”

“As long as possible. Sometimes longer.”

“What about you?”

“You mean, am I human? Certainly. I don’t believe I’m really old. I believe I’m quite attractive. I believe you seek out my company because you think I’m charming—even when you insist on turning the conversation to physics.”

“No! I mean it!”

“Well, I suspect Neville told you that the data I had gathered were not significant beyond the margin of error, which makes them doubtful, and that’s true enough.... And yet I prefer to believe they have the meaning I expected them to have to begin with.”

“Just because you want to believe that?”

“Not just because. Look at it this way. Suppose there is no harm in the Pump, but that I insist on thinking there is harm. In that case, I will turn out to be a fool and my scientific reputation will be badly damaged. But I am a fool in the eyes of the people who count, and I have no scientific reputation.”

“Why is that, Ben? You’ve hinted around the tale several times. Can’t you tell me the whole story?”

“You’d be surprised how little there is to tell. At the age of twenty-five I was still such a child that I had to amuse myself by insulting a fool for no reason other than that he was a fool. Since his folly was not his fault, I was the greater fool to do it. My insult drove him to heights he couldn’t possibly have scaled otherwise—”

“You’re talking of Hallam?”

“Yes, of course. And as he rose, I fell. And eventually, it dropped me to— the Moon.”

“Is that so bad?”

“No, I rather think it’s good. So let’s say he did me a favor, long-way round.... And let’s get back to what I’m talking about. I’ve just explained that if I believe the Pump to be harmful and am wrong, I lose nothing. On the other hand, if I believe the Pump to be harmless and am wrong, I will be helping to destroy the world. To be sure, I’ve lived most of my life already and I suppose I can argue myself into believing that I have no great cause to love humanity. However, only a few people have hurt me, and if I hurt everyone in return that is unconscionable usury.

“Then, too, if you’d rather have a less noble reason, Selene, consider my daughter. Just before I left for the Moon, she had applied for permission to have a child. She’ll probably get it and before long I’ll be—if you don’t mind my saying so—a grandfather. Somehow I’d like to see my grandchild have a normal life expectancy. So I prefer to believe the Pump is dangerous and to act on that belief.”