Analyze the Brutus-Cassius quarrel as a test of their friendship under pressure, and evaluate whether Brutus fits Aristotle's definition of the tragic hero by the play's end.
Act 4 tests Brutus and Cassius's friendship directly: now co-commanders of an army against Antony and the young Octavius, the two quarrel bitterly in Brutus's tent, Brutus accusing Cassius of corruption and both men nearly coming to blows, before reconciling as old friends who need each other far more than their pride wants to admit. In the same scene, Brutus reveals, with striking composure, that his wife Portia has died -- a controlled, almost stoic grief that says as much about Brutus's character under pressure as any speech could.
At the Battle of Philippi, Cassius receives a report from his servant that his friend Titinius has been captured by the enemy -- a mistaken reading of a distant, confusing skirmish, since Titinius has actually just been celebrating with allied troops. Believing all is now lost, Cassius has himself killed rather than face capture, a devastating piece of situational irony built entirely on incomplete information, the exact device studied earlier this year in "The Necklace" and "The Bet." When Titinius returns alive and finds Cassius dead over a misunderstanding, he too takes his own life. Brutus, ultimately defeated, falls on his own sword as well. Antony, arriving at the battlefield after the fighting ends, delivers the play's final judgment, calling Brutus the noblest Roman of them all -- explaining that Brutus alone among the conspirators acted from genuine belief in the common good rather than personal envy, the only character in the entire conspiracy whose motive the play ultimately validates as sincere.
Mastery looks like: They can explain the Brutus-Cassius quarrel and reconciliation, identify Cassius's death as situational irony, and construct an evidence-based argument for whether Brutus fits Aristotle's definition of the tragic hero.
Common stumbles: Missing that Cassius's death depends on a specific factual misunderstanding, and so describing it only as "sad" rather than naming the situational irony precisely; accepting Antony's final verdict on Brutus uncritically rather than weighing it against the rest of the play's evidence.
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