Gene ultimately caused Phineas' death because he was the only one in the timeline of events who deliberately harmed Phineas. He wanted Phineas to be injured because he felt that Phineas did not want him to do well academically. He was also much happier without Phineas around because in a way, Gene took Phineas' place. Gene obviously had many motives to cause Phineas' death, but he also had many ways he was responsible for his death.
             The doctor was not the cause of Phineas' death because he had intentions of helping Finny and making him better. He was also following routine procedure. However, after Gene caused Phineas to fall and break his leg for the first time, Finny's bone became weak. If Gene had not jounced the limb, then Finny's bone would not have been so weak from being broken that it would break the second time. In this case, the operation would have never had to happen and the bone marrow would have never flowed into Phineas' bloodstream, causing him to die.
             Brinker was not the cause of Phineas' death because he only called the meeting to prove that Gene had deliberately jounced the limb of the tree while Finny was on it. However, if Gene had just admitted to deliberately jouncing the limb Finny was on, causing him to fall, Brinker would have never called the meeting. On page 152, Brinker told Gene that he pitied Finny, and Gene responded by telling Brinker how wrong he was. When Brinker suggested that they do something about preventing Finny from pitying himself, Gene made it clear that Brinker didn't have his approval to do so. Gene challenged Brinker to calling the meeting by telling him how not to act towards Finny. If he had just let Brinker do as he pleased, Brinker would have never called the meeting, and Finny would have never fallen down the stairs.
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