 Why shouldn't Purnie stop time?
Purnie ran laughing and shouting through the forest until he could run no more. It was exactly as he knew it would be: the milky-orange stream had become motionless and its minute whirlpools had stopped whirling; a nearby bee hung suspended over a paka plant, its transparent wings frozen in position for a downward stroke; and the heavy purple fluid overhead held fast in its manufacture of whorls and nimbi. With everything around him in a state of perfect tableau, Purnie hurried toward the ocean. When Purnie had stopped time, the bees—like all the other creatures he met—had been arrested in their native activities, and he knew that as soon as he resumed time, everything would pick up where it had left off. Rather than spoil what was clearly going to be a perfect day, he chose to ignore the fact that he had been forbidden to use time-stopping as a convenience for journeying far from home. He chose to ignore the oft-repeated statement that an hour of time-stopping consumed more energy than a week of foot-racing. He chose to ignore the negative maxim that "small children who stop time without an adult being present, may not live to regret it." With it under his arm he bounded along a dozen more steps, then stopped abruptly in his tracks. Further down the beach was a pair of two-legged animals poised in mid-step, facing the spot where Purnie now stood. When he got no reaction, he remembered that he himself was "dead" to the living world: he was still in a zone of time-stopping, on the inside looking out. For him, the world would continue to be a tableau of mannikins until he resumed time. It was time itself that Purnie had stopped, not the world around him. He scampered around the rockpile and down the sandy cliff to meet the tripons who, to him, had just come to life. The tripon thought Purnie's feat was superb. Purnie ran from pillar to post, trying to see and do everything at once. Purnie's invitation got nothing more than startled glance from the animals who quickly returned to their chatter. The animals stopped so suddenly that Purnie nearly tangled himself in their heels. Sure, it's your money that put us here; it's your expedition all the way. As Purnie followed along, a leg shot out at him and missed. Purnie shrieked with joy at this new frolic and promptly stood on his head. When they stopped, Purnie stopped.
 Stopping time consumes massive amounts of energy.
 Small children who stop time, may not live to regret it.  Purnie may be abducted if the animals know he can stop time.  Purnie may not be able to get time going again.  Stopping time consumes massive amounts of energy.