the first stories about pantropy.) Simak's version of Jupiter is a cold, windswept, and corrosive hell where only advanced technology allows the station to exist at all. A scientist is accompanied by Towser, his tired and flea-bitten old dog. But there is a problem: Men permanently transformed to survive unaided on Jupiter's surface leave the station to gather data and inexplicably fail to return. Finally, the scientist transforms himself and his canine companion into the seal-like beings that can survive the surface. They leave the station in their new form and experience Jupiter as a paradise. Towser's fleas and irritations are gone and he is able to talk telepathically to his former master. Like the previously transformed station personnel, the scientist decides never to return. He eventually does return, to share with all humankind what he has discovered. It seems impossible – how can he show them the wondrous Jupiter that he and Towser perceive? Joe steps in again, once more out of sheer mischief. He knows a mind trick to allow people to broadcast meaning to others' minds as they speak. By means of a kaleidoscope-like instrument, he can twist the minds of other people so they can perform the mind trick. Thus all humanity learns the truth about Jupiter, and most elect to leave Earth, give up their physical humanity and live transformed on Jupiter's surface. Simak's vision of human apocalypse is unusual, not one of destruction, but simply of isolation. Much of humankind becomes so lonely that it eventually dies off. Some favor starting over as a completely different species capable of experiencing on Jupiter the simple bliss that humans have otherwise lost. Ten thousand years in the future, Jenkins is provided with a new body so he can better serve the few remaining "websters". By then, the dog civilization has spread all around the Earth, including the rest of the animals whom, little by little, the dogs introduce to their civilization. All of them are significantly intelligent, and Simak appears to mean that they were so all the while even though humans were not able to notice it. This civilization is a pacifist and vegetarian one. The dogs intervene in nature and distribute food to wild animals, managing to end virtually all predation. Besides, they also look for doors between dimensions through which some beings from different worlds are able to pass. At this point, a