He was a simulacron, of course, but so cleverly contrived that the human beings dealing with him had long since given up thinking of the real energy-entities, waiting in white-hot blaze in their field-enclosure "ship" miles from Earth.

The simulacron, with a majestic golden beard and deep brown, wide-set eyes, said gently, "We understand your hesitations and suspicions, and we can only continue to assure you we mean you no harm. We have, I think, presented you with proof that we inhabit the coronal haloes of O-spectra stars; that your own sun is too weak for us; while your planets are of solid matter and therefore completely and eternally alien to us."

The Terrestrial Negotiator (who was Secretary of Science and, by common consent, had been placed in charge of negotiations with the aliens) said, "But you have admitted we are now on one of your chief trade routes."

"Now that our new world of Kimmonoshek has developed new fields of protonic fluid, yes."

The Secretary said, "Well, here on Earth, positions on trade routes can gain military importance out of proportion to their intrinsic value. I can only repeat, then, that to gain our confidence you must tell us exactly why you need Jupiter."

And as always, when that question or a form of it was asked, the simulacron looked pained. "Secrecy is important. If the Lamberj people-"

"Exactly," said the Secretary. "To us it sounds like war. You and what you call the Lamberj people-"

The simulacron said hurriedly, "But we are offering you a most generous return. You have only colonized the inner planets of your system and we are not interested in those. We ask for the world you call Jupiter, which, I understand, your people can never expect to live on, or evenland on. Its size" (he laughed indulgently) "is too much for you."

The Secretary, who disliked the air of condescension, said stiffly, "The Jovian satellites are practical sites for colonization, however, and we intend to colonize them shortly."

"But the satellites will not be disturbed in any way. They are yours in every sense of the word. We ask only Jupiter itself, a completely useless world to you, and for that the return we offer is generous. Surely you realize that we could take your Jupiter, if we wished, without your permission. It is only that we prefer payment and a legal treaty. It will prevent disputes in the future. As you see, I'm being completely frank."

The Secretary said stubbornly, "Why do you need Jupiter?"

"The Lamberj-"

" Are you at war with the Lamberj?"

"It's not quite-"

"Because you see that if it is war and you establish some sort of fortified base on Jupiter, the Lamberj may, quite properly, resent that, and retaliate against us for granting you permission. We cannot allow ourselves to be involved in such a situation."

"Nor would I ask you to be involved. My word that no harm would come to you. Surely" (he kept coming back to it) "the return is generous. Enough power boxes each year to supply your world with a full year of power requirement."

The Secretary said, "On the understanding that future increases in power consumption will be met."

"Up to a figure five times the present total. Yes."

"Well, then, as I have said, I am a high official of the government and have been given considerable powers to deal with you-but not infinite power. I, myself, am inclined to trust you, but I could not accept your terms without understanding exactly why you want Jupiter. If the explanation is plausible and convincing, I could perhaps persuade our government and, through them, our people, to make the agreement. If I tried to make an agreement without such an explanation, I would simply be forced out of office and Earth would refuse to honor the agreement. You could then, as you say, take Jupiter by force, but you would be in illegal possession and you have said you don't wish that."

The simulacron clicked its tongue impatiently. "I cannot continue forever in this petty bickering. The Lamberj-" Again he stopped, then said, "Have I your word of honor that this is all not a device inspired by the Lamberj people to delay us until-"

"My word of honor," said the Secretary.

The Secretary of Science emerged, mopping his forehead and looking ten years younger. He said softly, "I told him his people could have it as soon as I obtained the President's formal approval. I don't think he'll object, or Congress, either. Good Lord, gentlemen, think of it; free power at our fingertips in return for a planet we could never use in any case."

The Secretary of Defense, growing purplish with objection, said, "But we had agreed that only a Mizzarett-Lamberj war could explain their need for Jupiter. Under those circumstances, and comparing their military potential with ours, a strict neutrality is essential."

"But there is no war, sir," said the Secretary of Science. "The simulacron presented an alternate explanation of their need for Jupiter so rational and plausible that I accepted at once. I think the President will agree with me, and you gentlemen, too, when you understand. In fact, I have here their plans for the new Jupiter, as it will soon appear."

The others rose from their seats, clamoring. " A new Jupiter?" gasped the Secretary of Defense.

"Not so different from the old, gentlemen," said the Secretary of Science. "Here are the sketches provided in form suitable for observation by matter beings such as ourselves."

He laid them down. The familiar banded planet was there before them on one of the sketches: yellow, pale green, and light brown with curled white streaks here and there and all against the speckled velvet background ofspace. But across the bands were streaks of blackness as velvet as the background, arranged in a curious pattern.

"That," said the Secretary of Science, "is the day side of the planet. The night side is shown in this sketch." (There, Jupiter was a thin crescent enclosing darkness, and within that darkness were the same thin streaks arranged in similar pattern, but in a phosphorescent glowing orange this time.)

"The marks," said the Secretary of Science, "are a purely optical phenomenon, I am told, which will not rotate with the planet, but will remain static in its atmospheric fringe."

"But what is it?" asked the Secretary of Commerce. "You see," said the Secretary of Science, "our solar system is now on one of their major trade routes. As many as seven of their ships pass within a few hundred million miles of the system in a single day, and each ship has the major planets under telescopic observation as they pass. Tourist curiosity, you know. Solid planets of any size are a marvel to them."

"What has that to do with these marks?"

"That is one form of their writing. Translated, those marks read: 'Use Mizzarett Ergone Vertices For Health and Glowing Heat.'"

"You mean Jupiter is to be an advertising billboard?" exploded the Secretary of Defense.

"Right. The Lamberj people, it seems, produce a competing ergone tablet, which accounts for the Mizzarett anxiety to establish full legal ownership of Jupiter-in case of Lamberj lawsuits. Fortunately, the Mizzaretts are novices at the advertising game, it appears."

"Why do you say that?" asked the Secretary of the Interior.

"Why, they neglected to set up a series of options on the other planets. The Jupiter billboard will be advertising our system, as well as their own project. And when the competing Lamberj people come storming in to check on the Mizzarett title to Jupiter, we will have Saturn to sell to them. With its rings. As we will be easily able to explain to them, the rings will make Saturn much the better spectacle."

"And therefore," said the Secretary of the Treasury, suddenly beaming, "worth a much better price."

And they all suddenly looked very cheerful.

BUY JUPITER was not my original title for the story. I am usually indignant when an editor changes the title I have given a story, and change it back when it appears in one of my own collections and then mutter about it in the commentary. -But not this time.

I called the story It Pays, an utterly undistinguished title. Bob Mills, without even consulting me, quietly changed it to BUY JUPITER and I fell in love with that as soon as the change came to my attention. To a punster like myself, it is the perfect title for the story-so perfect that I have given it to this entire collection, which, as you know, is BUY JUPITER AND OTHER STORIES.

Bob Mills gets the credit.

During those early years in which, with a certain amount of uneasy horror, I was watching my science fiction writing begin to fall off, I would occasionally get into a state of blue funk.

Could it be that I could no longer write science fiction at all? Suppose I wanted to write science fiction-could I?

I was driving down to Marshfield, Massachusetts, on July 23, 1958, to begin a three-week vacation which I dreaded (1 dread all vacations).I deliberately set about thinking up a plot to keep my mind off that vacation and to see if I could. A STATUE FOR FATHER was the result. I sold it to a new magazine, Satellite Science Fiction, and it appeared in the February 1959 issue.