nvestigations, but I'd like your personal feelings about him."

Harper's face sobered and he looked away a moment. "Cummins was as good
a guy as they come," he said. "But in a pinch he was just a weak sister.
That doesn't mean he didn't have a lot on the ball," Harper added
defensively. "He was a better pilot than most of us ever will be, but he
was just human like the rest of us."

"What do you mean, 'human'?"

"Weak, soft, failure when the going gets rough--everything we have to be
on guard against every minute we're alive."

"I take it you don't think much of human beings, as such."

Harper leaned forward earnestly. "Listen, Doc, when you've been around
ships as long as I have, you'll know what Captain West really meant. The
weakest link in any technological development has always been the men
involved with its operation. In space flight our weakness is pilots and
technicians. Set a machine on course and it'll go until it breaks
down--and flash you a warning before it fails. With a man, you never
know when he's going to fail, and you have to be on guard against _his_
breakdown every minute because he won't give any warning.

"Think what it's like to be in our shoes! We take the controls of a few
hundred million dollars worth of machinery, and we know that every last
man of us is booby-trapped with some weakness that can break out in a
critical moment and destroy everything. We fight against it; we struggle
to hold it in and act like responsible instruments. And we grow to hate
ourselves because of the weak things that we are.

"Cummins was like that. He fought himself every waking hour, knowing
that he had a weakness of becoming confused in a tight spot. Oh, it was
nothing that even showed up on the tests, and he was the best man of any
of us on the Base. But he knew it was there, just as we all know our
closets bulge with skeletons that we try to keep from breaking out."

"Do you fight yourself the way Cummins did?" Paul asked.

"Sure."

"What would happen if you pulled a blunder that wrecked that ship out
there on the stand."

"I'd have had it, that's all. I'd never get within ten miles of a rocket
base again as long as I lived. And there wouldn't be much worth living
for--"

"It would be pretty wonderful to feel you weren't constantly on the
verge of some disastrous blunder, wouldn't it?"

"It would be a rocket man's idea of heaven to handle these ships with
that kind of a feeling inside him."

"W