the contemplation of a great many risky alternatives in order to find the safest way to proceed.
There was scarcely a Three-Law robot on the planet who would have been willing to work on Snowball, let alone operate the simglobe to test ideas for bringing Comet Grieg in. Few robots would even be willing to help set up the problem, on the grounds that the simulation could pave the way for letting a real comet strike the real planet-which would be dangerous to humans in the extreme. Davlo had therefore ordered a custom-built robot for his Snowball work, and been glad to have him when he realized Grieg's potential.
It had taken a lot of argument and discussion with the robot designer, an exceedingly conservative gentleman who was most reluctant to put the slightest restriction on First Law, but the result was Constricted First Law 001-CFL-001. Tradition and convention would have required Davlo to named CFL-001 something like Caefal, or Cuffle, or even, as one waggish colleague suggested, Careful. But none of those appealed to Davlo, and he had come up with Kaelor instead.
But, either as a side effect of constricted First-Law potential, or merely as the consequence of the normal random subpathings of his positronic brain, Kaelor was also possessed of a dour, even depressive, outlook on life and the universe. "What are these assumptions, Kaelor?"
"You're assuming you can hold the comet together during the original guidance explosion," said Kaelor, "and then assuming you can split it apart in precisely the manner you wish, exactly when you wish. Furthermore, you have not resolved the issue of solar heating and its effects. I also have doubts about your being able to control the comet's outgassing. You have also been quite arbitrary about the number of fragments needed for the job, and, finally, you have not dealt with the incredibly delicate timing and guidance control needed for final-phase targeting and atmospheric entry. Success requires a degree of precision in all these matters that I see no way of accomplishing."
"I am aware of all those problems," said Davlo. "If we were only to begin after we had solved all the problems, we would never begin at all. But I have demonstrated that the basic plan will work. Or at least that it can. Now I just have to convince my superiors. But in my considered opinion, I have proved we can drop Comet Grieg onto Inferno, and save the planet."
"Granting your assumptions, I suppose you are right," the robot replied in dour tones. "I only wonder if you can manage to do it without killing everybody."
JUSTEN DEVRAY, COMMANDER of the Combined Inferno Police, sat in the unmarked and slightly battered aircar and watched the sun come up over parkland of idyllic green. He was tired. Deathly tired. But being tired was part of the job description on this duty. That was part of what he was here to learn.
It had seemed like a very sensible theory, going around to every bureau of the Combined Infernal Police, getting a firsthand idea of the sort of police work he had never had the chance to do, back in the old days. It had, in fact, been Justen's own idea, and it was teaching him a lot. Now he knew for certain that stakeout duty was both duller and more exhausting than he had thought possible. And he was starting to suspect that a nice, soft office job had more to recommend than he had realized.
Justen's unmarked aircar was parked a hundred meters or so away from the surface entrance to the vast underground complex known as Settlertown. The entrance itself was a mushroom-shaped arrangement, with a central pillar that contained the elevator shaft, and a wide, rounded, overhanging roof that spread out from the pillar to keep the weather off anyone waiting for a car down to the interior. The entrance shaft stood just inside the gate to the huge park the Settlers had built over their underground city. The landscaping of the park was all Settler work as well, of course, a demonstration of their skill in terraforming.
But the design of Settlertown did not concern Justen Devray. The job of the officer on this stakeout was to keep on a watch on the people going in and out of Settlertown. There were, of course, other entrances to the vast series of artificial caverns and chambers below. The CIP had watches on those, as well. But the main entrance was the real prize, at least according