Sigmund Freud divided the human psyche into three parts: the ego, the superego and the id; balance between the three was deemed essential for mental health. Over the course of Lord of the Flies, Ralph, Piggy and Jack increasingly personify the attitudes, ideals and drives of the ego, superego and id, respectively. The interactions between the boys at the beginning of the novel are different from those of the middle and end; the loss of balance between the boys is an important theme in the novel, as it explains the descent of the boys into savagery and reflects on modern...
seems best explained by the savagery of the id. At first, it seems as if Jack, the id, is balanced: Ralph's control and Piggy's rational thought keep his primal urges in check. But the boys are on a wild island, a setting conducive to primal urges: the sanctum of the id. From the island, Jack gains power and breaks away from the boys. Without the balance of Ralph and Piggy, Jack roams unchallenged. The boys grow savage and unthinking, free to explore the primal desires of the id, and free to lose all of what society defines as humanity.