William Golding uses Lord of The Flies to send a stark message about the potential for evil which, he suggests, exists in everyone. The first symbol, other than the title, which will only be revealed later, is the conch shell. Piggy is, significantly, the first person to recognize its value and how it can be used to call others. Piggy does not, however, want to blow the conch himself and is happy to explain the technique to Ralph. There is no mistaking its power as the air is "full of bird-clamor and echoes ringing" after Ralph manages to blow it successfully. The sound of the conch brings other boys out from the forest, including Jack and the choir boys "hidden by black cloaks."
In their discussions, Ralph recognizes the need for a "chief to decide things," and a vote soon nominates Ralph, "with the trumpet-thing," as chief. The unsaid influence of the conch, "most obscurely, yet most powerfully," cannot be denied. The conch, therefore, ensures a sense of order and allows the boys to maintain some sense of the civilization they intend to emulate. it is the conch which allows the boys to speak in turn and it is the conch which, when smashed to pieces as Piggy falls to his death, symbolizes the end of any form of civilization on the island. The conch begins to lose its power as Jack shows no respect for it and, once the conch is gone, Ralph has no hope of regaining a position of power.
Piggy's glasses are also a symbol as they are used to start the fire which will hopefully bring rescuers to their aid. At first Piggy willingly uses his glasses but, later, Jack cruelly seizes what's left of the glasses and shows his power over the group as he is able to reduce Ralph's effectiveness and reveal Piggy's weaknesses. Jack's position is strengthened when he is in possession of the glasses.
Fire is a symbol of hope but, when out of control, it brings destruction. At first the fire is a way for Ralph to show his domination and the importance of rescue. It is important to note that he says, in chapter five, "smoke is more important than the pig." However, this will change when Jack, having killed a pig, feels powerful and intends to "raid them and take fire." He is able to lure the boys with the promise of real food, not just fruit, to the point that even Piggy and Ralph go along.
Jack has already used his power by hiding behind face paint and he knows that he can manipulate the boys which is especially important to him after Ralph is voted as chief and not him. He also knows how scared the boys are of the so-called Beast or Beastie. He likes to dismiss the boys' fears but at the same time intensify them and, in chapter eight, he makes a significant move in sharpening a stick and defining his power in the form of a "gift" by placing the head of the pig he has slaughtered onto a stick. The flies it will attract are the inspiration behind the title; Jack brings out the worst in himself and Roger, and even Maurice, as they "furtively" admire the "skewered" carcass. The pig's head is the start of the frenzy which takes over the boys after Simon, also affected by the pig's head, realizes the evil in everyone but is, ironically, mistaken for the beast in the chaos that follows.