The most obvious of the themes in the novel Lord of the Flies by William Golding is the basic human need for civilization, for some type of social order. The story shows that laws and rules are necessary in society to keep primitive instincts from ruling human actions. When these rules aren't present, humans tend to act without thought or discipline, and their actions go against the basic ideals of morality.
In the beginning of the novel, a group of boys are stranded on an island after the airplane they were on crashes into the ocean. The first characters we meet are Ralph and Piggy, who discover the conch shell that calls all the other boys on the island together. At first, the boys develop their own society, their own personal type of civilization. Ralph is elected Chief of the tribe, and appoints Jack to be the leader of the hunters. A kind of democracy is decided on - everyone gets their chance to speak, and to vote on major issues, but the day-to-day decisions are left up to an elected official, in this case the Chief. For several days, this "government" is upheld by all the boys, and all the rules are followed. However, after a while, some of the boys begin to disobey the rules, even if only in small ways. The boys who were supposed to build the shelters went swimming instead, the fire wasn't kept up properly, the designated "latrines" were given up, and the boys relieved themselves all over the island and on the beach. These minor deviations from the rules seem unimportant, but once those small rules are broken the boys don't seem to mind breaking the important rules either. .
Laws and rules are definitely necessary to keep the darker side of human nature in line. When all elements of civilization disappear on the island, the boys revert to a more primitive part of their nature, and they turn into savages and anarchy replaces democracy. Society holds everyone together, and with out civilization and rules, the boy's ideals, values, and basic ideas of what is right and wrong are forgotten, and the evils of human nature emerge.