The major themes of Lord of the Flies reveal the inner fight between good and evil that faces all the boys as they are stranded on a deserted island without any guidance from "grown-ups." Their ability to distinguish rational thoughts from irrational actions is constantly challenged. At the outset, the boys are all civilized and ironically it is Jack who reminds them in chapter 2 that "After all, we're not savages. We're English." Jack is the first boy who will reveal that he is susceptible to primitive and inhumane behavior when he kills the pig. Painting his face allows Jack to be "liberated from shame and self-consciousness" (ch 4).
All the boys are innocent at the beginning as they are unaware of their subconscious desires and they are too young to recognize their own unchecked motivations. Some are more morally pure than others and the "littluns" represent that aspect of society that can be easily influenced. In chapter 4, the reader is told that "the mask compelled them."
Ralph is the chosen leader of the boys and is aware that shelter and a signal fire are the basis upon which they must found their camp. Rescue means everything but some boys are too overwhelmed by their freedom from adult supervision to realize that they are making a choice by not helping with the shelters or fire. In organizing their society, Ralph is no match for Jack's tempting offer of meat and fun. These boys gradually succumb to Jack's style of leadership, especially as talk of the beast intensifies and irrational thoughts dominate the discussion.
After Simon is killed due to the boys' instinctive behavior when they mistake Simon for the beast, it is not long before any sense of order is destroyed and the conch smashes and Piggy, the voice of reason, falls to his death. Even Ralph, who works so hard to maintain the kind of society his Navy commander father would expect, "wept for the end of innocence."