The Lord of the Flies suggests that the basic nature of mankind is evil and barbaric.
For example, while the boys tried to make a fire," Jack stole Piggys glasses and made a fire with them". He was so focused on making a fire that he didn't even care if he broke them or not. He was screaming and yelling about how he needs the glasses like a psychotic barbarian. In addition, when Jack doesn't like someone, he kills him just like,"[he] killed Simon." Jack tried to make it seem and sound like an accident, but all of the other boys already knew he was lying. The only thing wrong with his story is he didn't seem to be sorry about what he had done or had seen.
Barbaric nature was an everyday thing for the boys. When people got mad they count to ten, but when jack got mad,"[he] and his hunters started their own clan." The boys didn't stand a chance against the elements and fear for that matter alone; they needed Jack and his hunters to help them out if Jack wouldn't have had to be a leader and the best at everything, then they would have been found earlier.
In addition, Jack didn't know how to act around people," [he] would put on a mask and become a different person." When he put this mask on, he would become a barbaric monster, trying to kill everything around him. This mask was nothing more than some wood and paint and yet it would change him so much.
In closing, The Lord of the Flies expressed humanity as a bloodthirsty monster.