In Julius Caesar, why does Shakespeare present conflicting perspectives other than to create drama?
Shakespeare's play was about ancient Roman society -- a society that valued reason and logic over emotion and rash behaviour. Not only is he depicting the foibles of human nature in the conflicting characters' perspectives on law, governance and each other, but he is commenting on the Roman ideals.
Brutus is probably the character that most completely embodies the Roman ideals of logic, reason, honor, country before self. But, as the duelling funeral speeches show, the common people (the mob) were much more swayed by the emotionally charged (one might say manipulative) speech given by Antony. The people, in general, don't care so much for the high ideals of logic and reason, even in ancient Rome. They respond to the moment and are swayed by their emotions, even in which politician they will support.
Shakespeare, by showing us the downfall of ideals over emotional connection in ancient Rome, once again holds the mirror up to our modern society. We, certainly, as a mob of people, are as susceptible to following the emotion of the moment as were the ancient Romans listening to Antony on the steps of the Capitol.