Who is Phineas in A Separate Peace?

Phineas, also known as Finny, is one of the main characters in the novel "A Separate Peace" by John Knowles. He is charismatic, athletic, and popular, with a carefree and adventurous spirit. Finny's close friendship with the narrator, Gene Forrester, drives much of the plot as their relationship is tested during a time of heightened emotions and rivalries at a prep school during World War II.