The primary message that Golding is trying to convey throughout Lord of the Flies is that humans are inherently wicked, violent beings and will revert back to their primitive, savage instincts in an environment void of laws, restrictions, and order. Golding conveys this message by exploring the theme of civilization versus savagery, depicting the violent transformation of the civilized British schoolboys, and setting the story against the backdrop of a world war. Golding's personal experiences during WWII influenced his negative perception of humanity as he witnessed firsthand the destructive nature of mankind. The boys' harrowing, violent experience on the island is a microcosm of what is happening in the outside world.
In the story, Golding depicts the boys' significant transformation into savages by illustrating their refusal to follow Ralph's orders, their affinity for hunting pigs, and their complete disregard for the signal fire. Despite Ralph's attempt to establish a civil society, Jack undermines his authority and champions hunting pigs over completing essential tasks. Simon's enlightening interaction with the Lord of the Flies also conveys Golding's message and the true identity of the "beast" underscores his belief that all humans are inherently evil.
Important symbols like the signal fire, Piggy's glasses, and the conch shell gauge the boys' level of civility and depict their gradual regression. The reader recognizes that savagery reigns supreme once the signal fire goes out, Piggy's glasses are stolen, and the conch shell shatters. Under Jack's leadership, the boys paint their faces, develop a bloodlust, and contribute to the murders of Simon and Piggy.
By the end of the story, the savages hunt Ralph throughout the island and start a forest fire that threatens to destroy the entire island. The former innocent British schoolboys transform into bloodthirsty savages in an environment without adults, laws, and order. Their dramatic transformation and violent crimes convey Golding's main message that human beings are inherently wicked, violent beings and will embrace their primitive instincts if left to their own devices.