"There must be a catch to it somewhere," Short protested. He almost sounded indignant.
"There's a catch," Liddell said.
"Give."
"These stations. It's why they're manned. Don't you think the whole job could be done mechanically?"
"Yes, but—"
"But it's not, Mr. Short. Because there are too many variables. Because sub-space is still unpredictable and the thinking machine has not yet been built which can handle more than a few unpredictables."
"What are you getting at?"
"Just this, Mr. Short. You can kill us if you want to. You can choose your destination, wait while I plot it out on the de-materializer and possibly verify it for yourself if you know anything about sub-space."
"I don't know anything at all about sub-space," Short admitted.
"But," Liddell went on, "you'd be gambling and gambling badly with the unpredictability factor. One sub-space transfer out of two, according to statistics, is not routine. Oh, not essentially dangerous as long as there's someone at the transfer unit station to correct any inconsistencies in transfer as they arise. But if there's no one, you'll float in sub-space forever, not going hungry, not going thirsty, not growing older, but slowly going crazy with changelessness...."