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In Shakespeare's Julius Caesar, Caesar is a strong leader—very wise, a great strategist, and a valiant soldier who inspires respect. Caesar is not good about taking advice from others. For instance, on the Ides of March, Caesar's wife and the priests tell him he should not go out, but he allows Decius (secretly his enemy) to appeal to his ego so that Caesar goes anyway. Caesar expresses his conviction that he is always right—he is never wrong without good purpose, and he cannot be swayed to change his mind. This inflexibility does not endear him some people, like Cassius, Cinna, Metellus, Casca, and Decius—his murderers—who have asked him to free Publius Cimber.
But I am constant as the northern star,
Of whose true-fix'd and resting quality
There is no fellow in the firmament…
But there's but one in all doth hold his place.
So in the world, 'tis furnish'd well with men…
Yet in the number I do know but one
That unassailable holds on his rank,
Unshaked of motion; and that I am he… (III.i.66-76)
Antony is seen as a "playboy," but is a gifted speaker who can motivate even large crowds with his words, as we see when he turns the people against Brutus and the other killers—but he is not always honorable, and can be disrespectful and unkind.
Antony tells Brutus he won't judge him and the other murderers, but secretly vows to kill them all—instead of challenging Brutus to his face. He's sneaky in that he asks to meet with Brutus, demonstrates good will by shaking hands with the assassins, and pretends that he will consider their reasons for killing Caesar, but then betrays them at the funeral. Antony casually agrees to his nephew's death, and shows great disrespect for Lepidus, an older but "tried and valiant soldier." Antony says of Lepidus:
This is a slight unmeritable man,
Meet to be sent on errands (IV.i.12-13)
Brutus is a man of great passion who dearly loves Rome. He says he loves honor more than he fears death—and he deeply loves Caesar. However, he allows his fear for Rome's wellbeing under Caesar's leadership to compromise his integrity. In Act One, scene one, two tribunes, Flavius and Marullus hear the crowds' enthusiasm for Caesar; Flavius fears it will make Caesar believe he is greater than he is, and that Caesar will treat them like slaves. They are not alone: Brutus allows his concerns about Caesar to overshadow his better judgment by joining the conspirators committed to Caesar's death—for he is afraid that if Caesar is crowned king, he will change, acting like a snake: one they placed in power.
He would be crown'd:
How that might change his nature, there's the question. (II.i.12-14)
Cassius is an uncannily good judge of men and their capabilities. This shows itself as he plans Caesar's assassination. However, he is also shallow and jealous. Having once saved Caesar's life, he expects more respect from him. Because he has to bow when Caesar passes, he is envious and resentful.
…so from the waves of Tiber
Did I the tired Caesar. And this man
Is now become a god, and Cassius is
A wretched creature, and must bend his body
If Caesar carelessly but nod on him. (I.ii.120-124)
Cassius can work things to his advantage. For example, it is unclear if Cassius defers to Brutus from friendship or to keep...
...the credibility that the widely-respected Brutus brings to their cause.