to a Nipe not to perform such a ritual."

"Just so," Yoritomo agreed vigorously. "Such things, once established,
would tend to remain. But it is a characteristic of a ritual-taboo system
that it resists change. How, then, do you account for their high
technological achievements?"

"The pragmatic engineering approach, I imagine. If a thing works, it is
usable. If not, it isn't."

"Very good. Now it is my turn to lecture." He put his pipe in an ash tray
and held up a long, bony finger. "Firstly, we must remember that the Nipe
is equipped with an imagination. Secondly, he has in his memory a
tremendous amount of data, all ready at hand. He is capable of working out
theories in his head, you see. Like the ancient Greeks, he finds no need
to test such theories--_unless_ his thinking indicates that such an
experiment would yield something useful. Unlike the Greeks, he has no
aversion to experiment. But he sees no need for useless experiment,
either.

"Oh, he would learn, yes. But, once a given theory proved workable, how
resistant he would be to a new theory. How long--how _incredibly_ long--it
would take such a race to achieve the technology the Nipe now has!"

"Hundreds of thousands of years," said Stanton.

Yoritomo shook his head briskly. "Puh! Longer! Much longer!" He smiled
with satisfaction. "I estimate that the Nipe race first invented the steam
engine not less than ten million years ago." He kept smiling into the dead
silence that followed.

* * * * *

After a long minute, Scanton said: "What about atomic energy?"

"At least two million years ago. I do not think they have had the
interstellar drive more than fifty thousand years."

"No wonder our pet Nipe is so patient," Stanton said wonderingly. "I
wonder what their individual life span is."

"Not long, in comparison," said Yoritomo. "Perhaps no longer than our own,
perhaps five hundred years. Considering their handicaps, they have done
quite well. Quite well, indeed, for a race of illiterate cannibals."

"How's that again?" Stanton realized that the scientist was quite serious.

"Hadn't it occurred to you, my friend, that they must be cannibals? And
that they are very nearly illiterate?"

"No," Stanton admitted, "it hadn't."

"The Nipe, like Man, is omnivorous. Specialization tends to lead any race
up a blind alley, and dietary restrictions are a particularly pernicious
form of specialization. A lion would starve to