William Golding once said that in writing Lord of the Flies he aimed to trace society's flaws back to their source in human nature. By leaving a group of English schoolboys to fend for themselves on a remote jungle island, Golding creates a kind of human nature laboratory in order to examine what happens when the constraints of civilization vanish and raw human nature takes over. In Lord of the Flies, Golding argues that human nature, free from the constraints of society, draws people away from reason toward savagery.
The makeshift civilization the boys form in Lord of the Flies collapses under the weight of their innate savagery: rather than follow rules and work hard, they pursue fun, succumb to fear, and fall to violence. Golding's underlying argument is that human beings are savage by nature, and are moved by primal urges toward selfishness, brutality, and dominance over others. Though the boys think the beast lives in the jungle, Golding makes it clear that it lurks only in their hearts.
Although Golding argues that people are fundamentally savage, drawn toward pleasure and violence, human beings have successfully managed to create thriving civilizations for thousands of years. So that disproves Golding's theory about human nature being savage, right? Wrong. The famous psychologist Sigmund Freud argued that without the innate human capacity to repress desire, civilization would not exist. In Lord of the Flies, Golding makes a similar argument. He depicts civilization as a veil that through its rules and laws masks the evil within every individual. So even while civilizations thrive, they are merely hiding the beast. They have not destroyed it.
The Lord of the Flies is a chronicle of civilization giving way to the savagery within human nature, as boys shaped by the supremely civilized British society become savages guided only by fear, superstition, and desire. And even before the boy's become fully savage under Jack, Golding shows hints of the savage beast within society by showing Piggy's love of food, the way the boys laugh when Jack mocks Piggy, and all the boys' irrational fear of the "beast." And as the boys on the island shed civilization for savagery, the adults of the supposedly "civilized" world outside the island are engaged in a savage and brutal worldwide nuclear war.
The "beast" is a symbol Golding uses to represent the savage impulses lying deep within every human being. Civilization exists to suppress the beast. By keeping the natural human desire for power and violence to a minimum, civilization forces people to act responsibly and rationally, as boys like Piggy and Ralph do in Lord in the Flies. Savagery arises when civilization stops suppressing the beast: it's the beast unleashed. Savages not only acknowledge the beast, they thrive on it and worship it like a god. As Jack and his tribe become savages, they begin to believe the beast exists physically—they even leave it offerings to win its favor to ensure their protection. Civilization forces people to hide from their darkest impulses, to suppress them. Savages surrender to their darkest impulses, which they attribute to the demands of gods who require their obedience.
Most of the boys on the island either hide behind civilization, denying the beast's existence, or succumb to the beast's power by embracing savagery. But in Lord of the Flies, Golding presents an alternative to civilized suppression and beastly savagery. This is a life of religion and spiritual truth-seeking, in which men look into their own hearts, accept that there is a beast within, and face it squarely.
Simon occupies this role in Lord of the Flies, and in doing so he symbolizes all the great spiritual and religious men, from Jesus to Buddha to nameless mystics and shamans, who have sought to help other men accept and face the terrible fact that the beast they fear is themselves. Of all the boys, only Simon fights through his own fear to discover that the "beast" at the mountaintop is just a dead man. But when Simon returns with the news that there's no real beast, only the beast within, the other boys kill him. Not just the savages, not just the civilized boys—all the boys kill Simon, because all of the boys lack the courage Simon displayed in facing the beast.
Within the larger battle of civilization and savagery ravaging the boys's community on the island, Lord of the Flies also depicts in great detail the relationships and power dynamics between the boys. In particular, the novel shows how boys fight to belong and be respected by the other boys. The main way in which the boys seek this belonging and respect is to appear strong and powerful. And in order to appear strong and powerful, boys give in to the savage instinct to ignore, pick on, mock, or even physically abuse boys who are weaker than them. Over and over, Lord of the Flies shows instances where a boy who feels vulnerable will save himself by picking on a weaker boy.