When I read Lord of the Flies, I am struck by the representation the children are of stereotypical roles in an adult society.
I believe we see leaders who want to lead but aren't quite qualified, we see leaders who should lead but lack confidence, we see followers of all kinds, people who lack self-control, people who seek only good for themselves, and people who believe others should do the work for them.
I always end up leaving the book comparing character to others I see in real life, adults who mirror those roles. Then I think about myself. I take a look in the mirror and question who I might be in those situations and determine who I want to be, and how I hope people will see me.
Lord of the Flies is a classic example of a society gone wrong and everyone played a role in letting it get that way. Each of us should consider our own roles in the societies we live in.
If you are referring to the main idea of Lord of the Flies (the central theme) is the inner capability that every civilized human being has to single-handed overthrow power and return to its basic Id: Its most primitive,basic, and rouge form of behavior.
The loss of humanity is another laterall topic. As humans are represented by children in the story, it is even more shocking to see where desperation leads and how the sense of self can be lost forever if one is fighting against an uncivilized majority: Even Ralph lost some of his.
The author certainly shows a deep belief in his main idea, precisely because he used choirboys (the cream of the crop in terms of holy-looking youths) as the protagonists of a dilemma that challenged every canon of behavior, belief, religion and morality that could have been tested. And they mostly failed.