Jealousy causes many of the characters in The Tragedy of Julius Caesar to commit dangerous and foolish acts. Cassius' jealousy drives him to kill Caesar. All the conspirators, except the noble Brutus, kill Caesar because they feel threatened by his power. Brutus is the only conspirator who murders Caesar for more honorable reasons. Jealousy is a very important theme in this play.
Cassius feels very threatened by Caesar's power. He remembers when he was an equal to Caesar, and doesn't think that Caesar deserves this much power. He comments to Brutus, "I was born free as Caesar; so were you: / We both have fed as well, and we can both / Endure the winter's cold as well as he" (Act I, sc. II, 97-99). Cassius is also enraged because Caesar doesn't like him. Caesar suggests, "Yond Cassius has a lean and hungry look; / He thinks too much: such men are dangerous" (Act I, sc. II, 194-195). Cassius thinks that Caesar's temper is dangerous. He declares, "Ye gods! It doth amaze me, / A man of such a feeble temper should / So get the start of the majestic world, / And bear the palm alone" (Act I, sc. II, 128-131).
Casca also is jealous of Caesar. He is disgusted by Caesar's manipulation of the commoners. He describes it as "mere foolery" (Act I, sc. II, 235). Casca agrees with Cassius that Brutus is an essential part the conspiracy. He says, "O, he sits high in all the people's hearts; / And that which would appear offense in us, / His countenance, like richest alchemy, / Will change to virtue and to worthiness" (Act I, sc. III, 157-160).
Brutus is the only conspirator who does not act out of jealousy and envy. He is Caesar's friend, and holds a powerful position in Rome. Therefore, he has no reason to feel jealous of Caesar. Brutus makes his decision based on what is the best for Rome, and is tricked into believing that the other conspirators feel the same way. He comments, "What need we any spur but our own cause / To prick us to redress? What other bond / Than the secret Romans that have spoke the word, / And will not palter? And what other oath than honesty to honesty engaged / That this shall be, or we will fall for it" (Act II, sc. I, 123-128). Antony realizes that Brutus had honorable reasons for killing Caesar. After Brutus' suicide, Antony proclaims, "This was the noblest Roman of them all. / All the conspirators save only he / Did that they did in envy of Great Caesar" (Act V, sc. V, 68-70).
Brutus probably would not have participated in the murder of Caesar had it not been for the influence of the other conspirators. Cassius, although very jealous of Caesar, convinces Brutus that he is acting out of honor and respect for Rome. However, jealousy is what drove many of the conspirators to murder Caesar
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