let it
bother you. I regard it as just an intellectual curiosity. I've included
it in my next book on that basis."

A new voice broke in. "What is it, Dad? One of your ten-thousand-word
shaggy dog jokes?" This from Fred Grant, 16, student in the senior grade
at the Hortense Bartholemew High School, and an only child of Martin
Grant.

"A little more respect toward your father," Martin said with much
sternness.

"Yes, Father."

"It was my _theory_."

John Henderson said, "But, Martin, I don't know what to think now. Of
course there must be some fallacy that I've missed. The way things stand
though, I--" He chuckled uncomfortably. "I begin to doubt myself. I
can't quite classify it as an intellectual curiosity."

"What else can you do with it?" Martin said. "I know your trouble. It's
a common one. You have a tendency to believe things or disbelieve them.
Now you've been presented with something your intellect demands that you
believe, while your experience shouts, 'lie'."

"Is Fred able to understand it?" John asked, smiling at the youngster
with fond and unconscious condescension.

"Not yet," Fred smiled. "I'm still in high school."

"And if you don't want to flunk out you'd better be off to bed at once,"
Martin told him.

"Yes, Father. Good night, Dr. Henderson."

Fred's departure left a vacuum in the conversation that took a minute to
fill. John Henderson frowned himself back to where he had been before
the boy had arrived. When he got there he frowned even more, because it
was a state of mental confusion that seemed to have no way of being
resolved.

"Maybe we can get at it this way," he said. "Let's postulate that your
theory is the only logical basis on which reality can rest. B, quite
obviously reality does not rest on this basis. We could make C,
therefore, that reality doesn't rest on a logical basis. But that
doesn't seem to satisfy me. Maybe C could be--no--" He glanced at his
watch, lifted his eyebrows and stood up. "I really didn't know it was so
late. I'll have to be going, Martin. An eight o'clock lecture in the
morning."

Martin made a wry face. "You've awakened my own conscience. I have an
hour or two of work yet before bedtime."

The two men went to the front door. John said, "Thank your wife again
for me. Wonderful dinner. You're lucky, Martin, to have such a good
cook."

* * * * *

That had been six weeks before John Henderson vanished. Martin Grant