The Lord of the Flies is definitely a literary symbol, one that Golding uses to reinforce his theme of decay and corruption on the island. When Simon first sees the pig's head on a stick, Golding infuses the scene with harsh, disgusting imagery to emphasize the idea of decay:
"there was the head grinning amusedly in the strange daylight, ignoring the flies, the spilled guts, even ignoring the indignity of being spiked on a stick" (137).
Despite Golding's suggestion that the sow's head ignores these terrible details, Golding pointedly reminds the reader of them; the novel revolves around the boys' collective fall from grace and civilization, showing the reader the destructive force of man's inherent evil. Simon's scene with the Lord of the Flies is a visual manifestation of Golding's larger theme for the novel.