"Because the rest of us couldn't run things. Not for long, anyhow. It's all a question of power."

"Power?" Forrester said.

"Everything we have," Diana said, "is derived, directly or indirectly, from the workings of one machine. Though 'machine' is a long way from the right word for it--it bears about as much resemblance to what you think of as a machine as a television set does to a window. There just isn't a word for it in any language you know."

"And all the G.o.ds have to work the machine at once?"

"Something like that." Diana came back from the window and sat down facing him again. "It operates through the nervous systems of the beings in circuit with it, each one of them in contact with one of the power nodes of the machine. And if one of the nodes is unoccupied, then the machine's out of balance. It will run for a while, but eventually it will simply wreck itself. Every one of the fifteen nodes has to be occupied. Otherwise--chaos."

Forrester nodded. "So when Dionysus died--"

"We had to find a replacement in a hurry. The machine's been running out of balance for about as long as it can stand right now."

Forrester closed his eyes. "I'm not sure I get the picture."

"Well, look at it this way: suppose you have a wheel."

"All right," Forrester said obligingly. "I have a wheel."

"And this wheel has fifteen weights on it. They're s.p.a.ced equally around the rim, and the wheel's revolving at high speed."

Forrester kept his eyes closed. When he had the wheel nicely spinning, he said: "Okay. Now what?"

"Well," Diana said, "as long as the weights stay in place, the wheel spins evenly. But if you remove one of the weights, the wheel's out of balance. It starts to wobble."

Forrester took one of the weights (Dionysus, a rather large, jolly weight) off the wheel in his mind. It wobbled. "Right," he said.

"It can take the wobble for a little while. But unless the balance is restored in time, the wheel will eventually break."

Hurriedly, Forrester put Dionysus back on the wheel. The wobble stopped.

"Oh," he said. "I see."

"Our power machine works in that sort of way. That is, it requires all fifteen occupants. Dionysus has been dead for three years now, and that's about the outside limit. Unless he's replaced soon, the machine will be ruined."

Forrester opened his eyes. The wheel spun away and disappeared. "So you found me to replace Dionysus. I had to look like him, so the mortals wouldn't see any difference. And the psychological similarity--"

"That's right," Diana said. "It's the same as the wheel again. If you remove a weight, you've got to put back a weight of the same magnitude.

Otherwise, the wheel's still out of balance."

"And since the power machine works through the nervous system--"

"The governing factor is that similarity. You've got to be of the same magnitude as Dionysus. Of course, you don't have to be an _identical_ copy. The machine can be adjusted for _slight_ differences."

"I see," Forrester said. "And the fifteen power nodes--" Another idea occurred to him. "Wait a minute. If there are only fifteen power nodes, then how come there were so many different G.o.ds and G.o.ddesses among the Greeks? There were a lot more than fifteen back then."

"Of course there were," Diana said, "but they weren't real G.o.ds. As a matter of fact, some of them didn't really exist."

Forrester frowned. "How's that again?"

"They were just disguises for one of the regular fifteen. Aesculapius, for instance, the old G.o.d of medicine, was Hermes/Mercury in disguise--he took the name in honor of a physician of the time. He would have raised the man to demi-G.o.dhood, but Aesculapius died unexpectedly, and we thought taking his 'spirit' into the Pantheon was good public relations."

"How about the others?" Forrester said. "They weren't all disguises, were they?"

"Of course not. Some of them were demi-G.o.ds, just like yourself. Their power was derived, like yours, from the Pantheon instead of directly through the machine. And then there were the satyrs and centaurs, and suchlike beings. That was public relations, too--mainly Zeus' idea, I understand. The original Zeus, of course."

"Of course," Forrester said.

"The satyrs and such were artificial life-forms, created, maintained and controlled by the machine itself. It's equipped with what you might call a cybernetic brain--although that's pretty inadequate as a description.

Vulcan could do a better job of explaining."

"Perfectly all right. I don't understand that kind of thing anyhow."

"Well, in that case, let me put it this way. The machine controlled these artificial forms, but they could be taken over by any one of the G.o.ds or demi-G.o.ds for special purposes. As I say, it was public relations--and a good way to keep the populace impressed--and under control."

"The creatures aren't around nowadays," Forrester pointed out.

"Nowadays we don't need them," Diana said. "There are other methods--better public relations, I suppose."

Forrester didn't know he was going to ask his next question until he heard himself doing so. But it was the question he really wanted to ask; he knew that as soon as he knew he asked it.

"Why?" he said.

Diana looked at him with a puzzled expression. "Why? What do you mean?"

"Why go on being G.o.ds? Why dominate humanity?"

"I suppose I could answer your question with another question--why not?

But I won't. Instead, let me remind you of some things. Look what we've done during the last century. The great wars that wrecked Europe--you don't see any possibility of more of those, do you? And the threat of atomic war is gone, too, isn't it?"

"Well, yes," Forrester said, "but--"

"But we still have wars," Diana said. "Sure we do. The male animal just wouldn't be happy if he didn't have a chance to go out and get himself blown to bits once in a while. Don't ask _me_ to explain that--I'm not a male."

Forrester agreed silently. Diana was not a male. It was the most understated statement he had ever heard.

"But anyhow," Diana said, "they want wars, so they have wars. Mars sees that the wars stay small and keep within the Martian Conventions, though, so any really widespread damage or destruction, or any wanton attacks on civilians, are a thing of the past. And it's not only wars, kid. It's everything."

"What do you mean, everything?"

"Man needs a G.o.d, a personal G.o.d. When he doesn't have one ready to hand, he makes one up--and look at the havoc that has caused. A G.o.d of vengeance, a G.o.d who cheers you on to kill your enemies.... You've studied history. Tell me about the G.o.ds of various nations. Tell me about Thor and Baal and the original bloodthirsty Yahweh. People _need_ G.o.ds."

"Now wait a minute," Forrester objected. "The Chinese--"

"Oh, sure," Diana said. "There are exceptions. But you can't bank on the exceptions. If you want a reasonably safe, sane and happy humanity, then you'd better make sure your G.o.ds are not going to start screaming for war against the neighbors or against the infidels or against--well, against anybody and everybody. There's only one way to make sure, kid.

We've found that way. We _are_ the G.o.ds."

Forrester digested that one slowly. "It sounds great, but it's pretty altruistic. And while I don't want to impugn anybody's motives, it does seem to me that--"