Then, quite casually, Lessing lifted off his monitor. The children continued staring at the tower as the screen gave three or four violent bursts of green fire and went dark. The block tower fell with a crash.
Moments later Lessing was back in the observation room, leaving the children busily putting the tower back together. There was a little smile on his lips as he saw Melrose's face. "Perhaps you're beginning to see what I'm driving at," he said slowly.
"Yes," said Melrose. "I think I'm beginning to see." He scratched his jaw. "You think that it's adult psi-contact that drives the child's potential underground—that somehow adult contact acts like a damper, a sort of colossal candle-snuffer."
"That's what I think," said Lessing.
"How do you know those children didn't make you take off your monitor?"
Lessing blinked. "Why should they?"
"Maybe they enjoy the crash when the blocks fall down."
"But that wouldn't make any difference, would it? The blocks still fall down."
Melrose paced down the narrow room. "This is very good," he said suddenly, his v............