How does Golding represent Piggy as a true wise friend?

"Ralph wept for the end of innocence, the darkness of man's heart, and the fall through the air of the true, wise friend called Piggy."

Piggy never fails to support Ralph. He is loyal, intelligent, and helpful. When everyone else goes their own way, Piggy stands true. He puts himself at risk for his friend. In essence, at the end he gave his life for Ralph.