In the debate between leaders of the opposing armies in Shakespeare's Julius Caesar, Act Five, scene one, this segment allows the new leaders of Rome to address their anger at the slaughter of Caesar. The debate heightens the tension prior to battle. This is achieved by the insults that are hurled back and forth between the members of both sides in the battle that is about to commence. (We also note difficulties foreshadowed between Antony and Octavius as Antony asks him to fight on one side of the battle field, and Octavius insists on fighting on the other.) This squabbling increases tension, but also gives us some insight into our characters, specifically Cassius and Brutus, who were at the bottom of Caesar's murder, which divided the empire and caused civil war.
Cassius shows that his part in Caesar's assassination was selfish. In the following lines, he tells Brutus how different things would be right now if Cassius was Caesar (if Cassius could have killed Antony when Caesar was murdered):
Flatterers? Now, Brutus, thank yourself.
This tongue had not offended so today,
If Cassius might have ruled.
Cassius starts name calling again, with his comments directed at Octavius and Antony. Antony chides Cassius as if he were a child.
A peevish school boy, worthless of such honor,
Join'd with a masker and a reveller! (65)
Old Cassius still!
When Octavius and Brutus go at each other, Octavius claims that he is not destined to die at Brutus' hand, but Brutus explains that Octavius could not hope to die in a more noble manner because those Octavius fights with are not noble at all.
Brutus had to be manipulated by Cassius to be a participant in Caesar's murder, and he did it only because he was convinced that Caesar did not have the well-being of Rome in his heart (Cassius lied to Brutus): Brutus, all along has cared for nothing but the safety of Rome. He is willing to sacrifice himself for the good of Rome.
So I hope, (60)
I was not born to die on Brutus' sword.
O, if thou wert the noblest of thy strain,
Young man, thou couldst not die more honorable.
While the arguing creates tension as Shakespeare has representatives of the two warring sides hurling insults at each other, we also can take a more personal interest in these men by knowing what has motivated them.
In Cassius's case, he is a child who begrudged all that Caesar had. However, Brutus cares nothing for himself, only for Rome. All of this information intensifies the mood as the battle looms ahead for the characters of Julius Caesar.