of distinguishing one individual from
another, but they can't tell whether a given individual is a space
pilot or a janitor. In fact--"

I marked the salient points in his speech. The MG-YR-7 would be
strictly a one-man ship. It had a built-in dog attitude--friendly
toward all humans, but loyal only to its master. Of course, it was
likely that the ship would outlast its master, so its loyalties could
be changed, but only by the use of special switching keys.

The robotics boys still weren't sure why the first six had gone
insane, but they were fairly certain that the primary cause was the
matter of too many masters. The brilliant biophysicist, Asenion, who
promulgated the Three Laws of Robotics in the last century, had shown
in his writings that they were unattainable ideals--that they only
told what a perfect robot _should_ be, not what a robot actually was.

[Illustration]

The First Law, for instance, would forbid a robot to harm a human
being, either by action or inaction. But, as Asenion showed, a robot
could be faced with a situation which allowed for only two possible
decisions, both of which required that a human being be harmed. In
such a case, the robot goes insane.

I found myself speculating what sort of situation, what sort of
Asenion paradox, had confronted those first six ships. And whether it
had been by accident or design. Not that the McGuire robots had been
built in strict accord with the Laws of Robotics; that was impossible
on the face of it. But no matter how a perfectly logical machine is
built, the human mind can figure out a way to goof it up because the
human mind is capable of transcending logic.

* * * * *

The McGuire ship was a little beauty. A nice, sleek, needle, capable
of atmospheric as well as spatial navigation, with a mirror-polished,
beryl-blue surface all over the sixty-five feet of her--or
his?--length.

It was standing upright on the surface of the planetoid, a shining
needle in the shifting sunlight, limned against the star-filled
darkness of space. We looked at it through the transparent viewport,
and then took the flexible tube that led to the air lock of the ship.

The ship was just as beautiful inside as it was outside. Neat,
compact, and efficient. The control room--if such it could be
called--was like no control room I'd ever seen before. Just an
acceleration couch and observation instruments. Midguard explained
that it wasn't ne