"Seems like a waste when what we had was working perfectly."
"We had to do it if we want to get to Centauri before they do." He jerked his head to indicate out there.
"But what good is it? The librarian is just a——" She closed her mouth.
"Just a memory system? That's what we need to duplicate the drive they have. Of course the librarian remembers the wrong thing but we're changing that."
"Can't we do it in some other way?"
"Not in time with the facilities we have. Maybe Nona could but the rest of us are just humans."
"Well, what's wrong with her?"
"Nothing. If you can get her interested in building a control unit I'll step aside."
"Why build it? She is the control."
"Now she is, but there are a number of reasons why a mechanical control is better. For one thing we don't know how much of her attention it requires. The drive may not function at all when she isn't consciously thinking about it."