He knows that the beast is inside of them. In other words that the beast they believe is out there is actually the evil inside of them.
Simon suggests that perhaps there is a beast and that it might be the boys themselves but because of his fear of public speaking he is unable to express this idea in a way which the rest of the boys can accept.
In "Lord of the Flies," it is Simon who is tending the fire when the boys' fear of the beast emerges. As the boys mistake a dead paratrooper for the beast and flee, Simon remains at the scene and discovers the truth about the figure on the mountain.
Simon discovers that the apelike beast the boys fear is actually the rotting corpse of a dead paratrooper, whose body has become entangled in the rocks and vines on the mountain. This realization causes Simon to understand the true nature of the beast as a manifestation of the boys' own inner darkness and fears.
The boys mistakenly kill Simon, a member of their group, mistaking him for the beast during a chaotic and frenzied moment. Simon had come down from the mountain, where he had discovered the truth about the supposed beast, but the boys, caught up in their fear and mob mentality, attack and kill him.
The "beast" that the boys kill is actually Simon, a member of their group. This is particularly tragic because Simon represents goodness and innocence, but is mistaken for the beast due to the hysteria and fear that has consumed the boys. Killing Simon represents the ultimate loss of humanity and descent into savagery for the boys, leading to irreversible consequences for everyone on the island.
Simon suspects that the beast the boys fear is actually their own inner darkness and capacity for evil. While the others don't grasp this concept and believe the beast is a physical entity, Simon realizes that it is a symbol of the darkness within themselves.
they killed simon because they believed he was the beast
The identical twin brothers are called Sam and Eric, or Samneric for short, not Simon and Eric. In chapter 6: Beast From air Samneric simultaneously describe the beast, and I quote.... "It was furry. There was something moving behind its head--wings. the beast moved too---" "that was awful. It kind of sat up---" "There were eyes---" "Teeth---" "Claws--" "The beast followed us---" "I saw it slinking behind the trees---"
Simon does not believe Sam and Eric's story about the "beast" being a physical threat. He understands that the beast is a manifestation of the boys' fear and inner darkness, rather than an external monster. Simon tries to convey this understanding to the group, but is ultimately killed before he can do so.
In "Lord of the Flies," the paradox is the boys fear of an external beast, when in actuality it rests within each of them, growing more dangerous by the day. They create a fantasy outer beast because they are not yet ready to face what they have become. Simon understands before the others just who and what the beast is, but at the point when they are killing Simon, it becomes clear, that they understand there is no outer beast. He is killed for trying to break the illusion.
Simon believes that the beast is not a physical entity but something that exists within each of the boys, representing their inner darkness and savagery. He tries to convey this message to the others, emphasizing the idea that the real beast is the evil and fear that resides within themselves.
beast a violent animals,bt their only fear is wht they are a beast.