cted with this
project. What does a psychologist have to do with robots? If you'll
pardon my ignorance."

This time she laughed softly, and Mike thought dizzily of the gay
chiming of silver bells. He clamped down firmly on the romantic
wanderings of his mind as she started her explanation.

"I'm a specialist in child psychology, Mike. Actually, I was hired as an
experiment--or, rather, as the result of a wild guess that happened to
work. You see, the first two times Snookums' brain was activated, the
circuits became disoriented."

"You mean," said Mike the Angel, "they went nuts."

She laughed again. "Don't let Fitz hear you say that. He'll tell you
that 'the circuits exceeded their optimum randomity limit.'"

Mike grinned, remembering the time he had driven a robot brain daffy by
bluffing it at poker. "How did that happen?"

"Well, we don't know all the details, but it seems to have something to
do with the slow recovery rate that's necessary for learning. Do you
know anything about Lagerglocke's Principle?"

"Fitzhugh mentioned something about it in the briefing we got before
take-off. Something about a bit of learning being an inelastic rebound."

"That's it. You take a steel ball, for instance, and drop it on a steel
plate from a height of three or four feet. It bounces--almost perfect
elasticity. The next time you drop it, it does the same thing. It hasn't
learned anything.

"But if you drop a lead ball, it doesn't bounce as much, and it will
flatten at the point of contact. _The next time it falls on that flat
side, its behavior will be different._ It has learned something."

Mike rubbed the tip of an index finger over his chin. "These
illustrations are analogues of the human mind?"

"That's right. Some people have minds like steel balls. They can learn,
but you have to hit them pretty hard to make them do it. On the other
hand, some people have minds like glass balls: They can't learn at all.
If you hit them hard enough to make a real impression, they simply
shatter."

"All right. Now what has this got to do with you and Snookums?"

"Patience, boy, patience," Leda said with a grin. "Actually, the
lead-ball analogy is much too simple. An intelligent mind has to have
time to partially recover, you see. Hit it with too many shocks, one
right after another, and it either collapses or refuses to learn or
both.

"The first two times the brain was activated, the roboticists just began
feeding data into