Simon's death may be considered to be the climax of the novel as it comes with such high drama amidst the boys whipping themselves into a frenzy as they dance and chant their 'song' in a terrible storm.
Certainly at first glance Simon's death could be attributed to Jack. It was he who had encouraged the boys to shed all the binds of civilized behaviour and to celebrate the act of killing and spilling of blood. He had spurred the boys on to the point where a dangerous mob mentality had developed; so powerful that even the most sensible of the group (Ralph and Piggy) were sucked into its bloodthirsty excitement. Jack was very much at the centre of this, "...and Jack, painted and garlanded, sat there like an idol." (p. 183).
To a lesser extent it could be argued that Ralph's failure of leadership led to such a chaotic scene on the night of Simon's death. Had he been a more decisive, better organized leader able to stand up to Jack's impetuous nature earlier on then perhaps the group of boys would have stayed united and the whole tragedy could have been avoided. Certainly it is hard to apportion blame on Simon himself as he was only bursting with desperation to bring the truth of 'the beast' to the entire group.
In the final analysis it was of course the whole group who so brutally mauled Simon to death. However, mobs are inevitably ugly, and a group of young boys in a setting knowing no adult supervision and instead succumbing to the base instincts of a despot peer (Jack) would of course be a highly dangerous social situation.
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