ns. The first step in the solution of this problem is to find the
most appropriate operator. Teddy?"

"I have an operator--of sorts," Theodora said. "I've been hoping one of
us could find a better."

"What is it?" Hilton demanded.

"The word 'until'."

"Teddy, you're a _sweetheart_!" Hilton exclaimed.

"How can 'until' be a mathematical operator?" Sandra asked.

"Easily." Hilton was already deep in thought. "This hard conditioning
was to last only _until_ the Masters returned. Then they'd break it. So
all we have to do is figure out how a Master would do it."

"That's _all_," Kincaid said, meaningly.

Hilton pondered. Then, "Listen, all of you. I may have to try a colossal
job of bluffing...."

"Just what would you call 'colossal' after what you did to the Navy?"
Karns asked.

"That was a sure thing. This isn't. You see, to find out whether Laro is
really an immovable object, I've got to make like an irresistible force,
which I ain't. I don't know what I'm going to do; I'll have to roll it
as I go along. So all of you keep on your toes and back any play I
make. Here they come."

The Omans came in and Hilton faced Laro, eyes to eyes. "Laro," he said,
"you refused to obey my direct order. Your reasoning seems to be that,
whether the Masters wish it or not, you Omans will block any changes
whatever in the _status quo_ throughout all time to come. In other
words, you deny the fact that Masters are in fact your Masters."

"But that is not exactly it, Master. The Masters ..."

"That is it. _Exactly_ it. Either you are the Master here or you are
not. That is a point to which your two-value logic can be strictly
applied. You are wilfully neglecting the word 'until'. This stasis was
to exist only _until_ the Masters returned. Are we Masters? Have we
returned? Note well: Upon that one word 'until' may depend the length of
time your Oman race will continue to exist."

The Omans flinched; the humans gasped.

"But more of that later," Hilton went on, unmoved. "Your ancient
Masters, being short-lived like us, changed materially with time, did
they not? And you changed with them?"

"But we did not change ourselves, Master. The Masters ..."

"You did change yourselves. The Masters changed only the prototype
brain. They ordered you to change yourselves and you obeyed their
orders. We order you to change and you refuse to obey our orders. We
have changed greatly from our ancestors. Right?"

"That is right, Master."