Piggy's first concern is to learn everyone's name and to have a meeting. He tells Ralph he doesn't care what they call him as long as it is not Piggy. Unfortunately, this is exactly what he becomes known as. He is also worried about his asthma and this is why he won't swim in the lagoon. We begin to see that he is physically weak but mentally strong. Piggy is also concerned that they won't be rescued. They have seen no sign of adults on the island and Piggy recalls the pilot talking about an atomic bomb and that everyone is dead. Ralph, on the other hand, is just taking time to enjoy how pleasant and beautiful the island is. Piggy keeps repeating that they have to do something. He thinks they need to organize; he needs some type of order to feel safe.
He is already establishing himself as a responsible, wise, and thoughtful person. His main concern is getting the boys together and establishing some kind of order. When he and Ralph find the conch, he explains that they can use it to summon the boys to a meeting. And from this point on, the conch becomes a means to create and sustain order on the island. The conch becomes a symbol of order. Piggy believes in what the conch can do.
Piggy's ability to think and reason is a burden because he understands more quickly than the other boys how the decisions they make will affect their ability to survive. Piggy tries to convince the others that rules and order are necessary, but he's ignored by most of the boys and teased by some of them just because "mocking him makes the others feel cheerful." He realizes the "beast" isn't real and isn't afraid of it, but he is afraid of people and what they're capable of doing. His loyalty to Ralph doesn't diminish, and he's invaluable to Jack as an advisor. Ralph wouldn't have remained a leader as long as he did without Piggy's intelligence, and it seems that Jack realizes this because he treats Piggy shamefully. Piggy sees the savagery in Jack and fears what Jack might do. The only way for Piggy to live with Simon's death is to deny what really happened to Simon. Just before his death, while holding the conch, Piggy appeals to the boys to stop and think whether they want to abide by civilized rules and laws or whether they want to committ murder and "break things up". Piggy's desire for reason, order, and his loyalty to Ralph ultimately lead to his death.