tever large
carnivore passes for a tiger on their home planet. This Nipe, let us
say, has never seen a tiger before, so he does not observe that this
particular tiger is old, ill, and weak. It is, as a matter of fact, on
its last legs. Our primordial Nipe hits it on the head, and it drops
dead. He drags the body home for the family to feed upon.

"'How did you kill it, Papa?'

"'Why, it was the simplest thing in the world, my child. I walked up to
it, bashed it firmly on the noggin, and it died. That is the way to kill
tigers.'"

Yoritomo smiled. "It is also a good way to kill Nipes. Eh?" He took the
towel and wiped Stanton's brow again.

"The error," he continued, "was made when Papa Nipe made the
generalization from _one_ tiger to _all_ tigers. If tigers were rare,
this erroneous bit of lore might be passed on for many generations
unchecked and spread through the Nipe community as time passed. Those
who did learn that most tigers are _not_ conquered by walking up to them
and hitting them on the noggin undoubtedly died before they could pass
this new bit of information on. Then, perhaps, one day a Nipe survived
the ordeal. His mind now contained conflicting information which must be
resolved. He _knows_ that tigers are killed in this way. He also
_knows_ that this one was not so obliging as to die. What is wrong? Ha!
He has the solution! Plainly, _this_ particular beast _was not a
tiger_!"

"How does he explain that to the others?" Stanton asked.

"What does he tell his children?" Yoritomo asked rhetorically. "Why,
first he tells them how tigers are killed. You walk up to one and bash
it on the head. But then he warns his little Nipelets that there is an
animal around that looks _just like_ a tiger, but it is _not_ a tiger.
One should not make the mistake of thinking it _is_ a tiger or one will
get oneself badly hurt. Now, since the only way to tell the true tiger
from the false is to give it a hit on the head, and since that test may
prove rather injurious, if not absolutely fatal, to the Nipe who tries
it, it follows that one is better off if one scrupulously avoids all
animals that look like tigers. You see?"

"Yeah," said Stanton. "Some snarks are boojums."

"Exactly! Thank you for that allusion," Yoritomo said with a smile. "I
must remember to use it in my report."

"It seems to me to follow," Stanton said musingly, "that there would
inevitably be some things that they'd never learn the truth about, onc