Lord of the Flies is an attempt to trace the defects of society back to the defects of human nature. Before the war, most Europeans believed that man could be perfected by perfecting his society. Golding saw a lot in the war which he claims couldn't be accounted for except on the basis of original evil. (Reilly 140-141).
Simon is the Christ-figure, the voice of revelation. He was one of the original choirboys. He goes into the jungle to pray, to build a church. He alone speaks to the beast, the Lord of the flies, and learns that the beast is not something outside of man but is an actual part of man, always close to man and hence not something to be killed or run away from. (Spitz 24-25). He had been the first to anticipate this: Maybe there is a beast. Maybe it's only us. Like Moses, he comes down from the mountain bearing the truth which in Simon's case is that the beast is Man himself, the boys' (and man's) own natures. But when he comes out of the darkness, bringing the truth, he is not heard for what ordinary man can live with so terrible an understanding? Like Jesus, he is killed. (Spitz. 24-5) .
Piggy is the voice of reason. He is the outsider. He alone shows marks of intelligence; he can think; he has brains. When he wears his spectacles he can see. Those same spectacles not only shed light; they make possible the lighting of the fire which is meant to be seen. And when he is deprived of those spectacles, he loses his rationality too. He has a sense of what is required for society. Playing is absurd to Piggy. He refuses to enter this imaginary universe which appears as the negation of common sense, thought, responsibility and worry. (Talon 297).
Piggy calls for order and justice and to put first things first and act proper". According to David Spitz:.
It is the practical Piggy who jarringly introduces the reality principle into this dream of pleasure: `How can you expect to be rescued if you don't put first things first and act proper?' The grammatical solecism should not conceal the psychological wisdom.