Gault took up a book, held it so that a shadow fell onto the
surface of the desk.

"That shadow," he said, "is two dimensional, has length and
breadth, but no thickness. Now in order to enter the third
dimension, our plane, the shadow would have to bulge out in some
way, into the dimension of thickness an obvious impossibility.
Similarly, we can not enter the fourth dimension. Do you see?"

"No!" retorted Pillbot with some heat. "In the first place, we
are not two dimensional shadows, and--why, what is the matter?"

Professor Gault's lanky form had stiffened, his near sighted eyes
glaring out over the laboratory to the rear of Pillbot. The
psychiatrist wheeled around, followed his host's gaze.

It was Harper. That young man's antics drew an amazed grunt from
Pillbot. He was describing peculiar motions in the air with his
pencil. Circles, whorls, angles, abrupt jabs forward. He bent
over the paper on the desk, made a few sweeps of the pencil, then
the pencil rose again into the air to describe more erratic
motions. Harper himself seemed in a trance.

Suddenly Pillbot gave a stifled gasp. It seemed to him that
Harper's arm vanished at the elbow as it stabbed forward, then
reappeared. Once again the phenomenon happened.

Pillbot blinked rapidly, rubbed his eyes. It must have been
illusion, he decided. It was too ... unlikely....

"Harper!" Gault's voice was like the snapping of a steel trap.

Startled, Harper came to with a jerk. Seeing he was being
watched, he flushed redly, then bent over his charts again. An
apologetic murmur floated from his desk.

"What was he doing?" Pillbot asked puzzledly.

"Doodling!" Gault spat out the word disgustedly.

"Doodling?" echoed the psychiatrist. "Why that is a slang term we
use in psychiatry, to describe the absent-minded scrawls and
designs people make while their attention is elsewhere occupied.
An overflow of the unconscious mind, we call it. Many famous
people are 'doodlers.' Their doodles often are a sign of special
ability--"

"Exactly!" snapped Gault. "It shows a special ability to waste
time. And Harper has become worse since I hired him to do some of
my mathematical work. Some influence in this laboratory--I blush
to confess--seems to bring it on. 'Four dimensional doodling' we
call it, because, as you saw, he doesn't confine it to the
surface of the paper!"

Pillbot looked startled. "By jove," he cried. "I believe you've
hit on something new to psychiatry