Golding uses setting in "Lord of the Flies" to show how it affects the boys' behavior in their new society. Golding specifically chose the uninhabited island for several reasons. Because there is no other civilized life on the island, the boys must make their own decisions about their fates. The boys realize this after they have all been assembled by Ralph, and Jack says, "Then we'll have to look after ourselves" (Golding, 21). The island is isolated from any other type of organized society and the boys begin to use pieces of their old society to make a new one. Ralph tries to preserve his former society by trying to regulate everything, such as the fire, shelters, and meetings. Jack, on the other hand, just wants to have fun, and a power struggle ensues between the two leaders. The isolation of the boys brings out negative qualities in Jack; his killer instinct and the accompanying ruthlessness. The killer instinct begins to show when Jack goes hunting for pigs in the beginning of the novel. Shortly after his first unsuccessful hunt, he becomes completely engrossed in killing: "he tried to convey the compulsion to track down and kill that was swallowing him up" (51). When he gets his first kill, he relishes the victory over the pig and becomes completely ruthless towards animals as well as the other boys. Pigs are a way for Golding to show the growth of Jack's negative qualities through his actions to them. Jack steps over the threshold from hunting to cruelty when he kills the sow in a gruesome way, and places its head on a stick. After that, he is open to other acts of cruelty, such a killing Piggy and torturing Samneric.
Roger, Jack's friend, also develops his sadistic tendencies because of his separation from society. At first he is reluctant to embrace his savage callings:
"Roger gathered a handful of stones and began to throw them. Yet there was a space round Henry, perhaps six yards in diameter, into which he dare not throw. Here, invisible yet strong, was the taboo of the old life. Round the squatting child was the protection of parents and school and policemen and the law" (62).
Roger's morals are still intact, but the cracks are beginning to show. Throughout the book, Roger succumbs more and more to the underlying cruelty in his heart. He finally joins Jack's tribe and is instantly recognized as the chief "executioner." He is the one who gruesomely kills the sow and then prepares Ralph's death for him, as "a stick sharpened on both ends" (190), an allusion to the killing of the sow. Upon joining Jack's tribe, Roger realizes that the lack of organized society and their exclusion from the outside world frees him from morality, leading him to become the torturer and enforcer of Jack's laws. Golding uses Jack and Roger to exemplify the natural savage tendencies and negative qualities...