eturned with a grin.

"Third, the Blue Ghost led Scotty and me on a wild chase that ended up
with me dropping into the quarry. The facts are that the ghost somehow
triggered the plane alarm. We will not argue whether or not a real ghost
could have set off a purely physical, nonspiritual alarm."

Barby nodded soberly, but there was a twinkle in her blue eyes.

"Continuing with the facts of that incident, the ghost stayed ahead of
us without difficulty. A real ghost could have done that, I suppose, but
so could any person in reasonable physical shape who knew the terrain.
Now, the ghost's light went off as he reached the edge of the quarry, or
somewhere in the vicinity of the edge."

Rick looked at his sister. "I will stipulate that a real ghost need not
have any reason for his actions. But a person imitating a ghost would
have had to turn off his light in order to go around the quarry,
otherwise we would have seen that he made a detour. A ghost would
presumably float right over the quarry."

"Ghosts do float," Barby agreed solemnly.

"Uh-uh. Since this one did not, and since it reappeared--or the light
did--on the opposite side of the quarry, we believe there was a
deliberate attempt to lead us into said quarry."

He paused and took a deep breath. "How am I doing, coach?"

Dr. Miller nodded approval. "Fine. See how easy it is to separate fact
and conjecture?"

"So what do we conclude from this one event? We conclude it is
reasonable to believe that a person, and not a spook, triggered the
plane alarm and led us to the quarry. We speculate that the person did
not know about the alarm and set it off by accident, probably while
inspecting the plane, since we see nothing to be gained by sabotage. We
speculate that the chase was to frighten us, not primarily to harm us,
the reason being that we rushed the ghost during the ghost act and are
therefore potentially dangerous. We reach this conclusion because the
ghost picked a side of the quarry where we would land in the water,
which is plenty deep by the way, and not on the rocks."

"Okay. Scotty, take over. I'm worn out from trying to be precise."

The scientist grinned. "Lack of practice, I'm afraid. If we all sought
precision in our speech many of the world's misunderstandings could be
avoided."

"I don't know what we can say," Scotty objected. "We have few facts. We
have only some observations. We can try to interpret our observations,
but we can't prove them.