Who is the protagonist of the story? Describe them? In the bully book​

Bill is the leader and most self-assured member of the Losers Club as well as the main protagonist of the story. Feeling responsible for Georgie's death, he seeks revenge on the monster.https://en.m.wikipedia.org › wiki › I...

As this shows, once a self-contradiction is shown, the convention for writing an Indirect Proof is to then quit the indented sequence and write just the conclusion, followed by the justification “IP.” This means that the Indirect Proof has been accomplished: by showing that the assumption led to a self-contradiction