The concept of honor pervades almost every action in Julius Caesar, especially those of that “honorable man” Brutus. Speaking of the “basic paradox in Brutus’s motive,” Norman Council points out that “he is so firmly committed to honour that although typically, for a sixteenth-century man of honor, prepared to risk death for its sake, he also assumes that his honorable instincts will inevitably enable him to serve ‘the general good’” (When Honour’s at the Stake: Ideas of Honour in Shakespeare’s Plays [New York: Barnes & Noble Books, 1973], 61).
It might be more accurate to say that Brutus is so firmly committed to himself and so proud of his honor that he cannot clearly see the “general good,” cannot even see beyond his desire to appear honorable. And it is this vain (in two senses of that word) approach to honor which leads to Brutus’s downfall.
Brutus’s self-absorption is evident practically from the moment he begins to speak. He explains to Cassius: “Nor construe any further my neglect / Than that poor Brutus, with himself at war, / Forgets the shows of love to other men” (The Folger Library General Reader’s Shakespeare: Julius Caesar, eds. Louis B. Wright and Virginia A. LaMar [New York: Washington Square Press, 1959], 1.2.50-2). There are indications that Brutus’s introspections have their root in a point of honor—Caesar’s ambitions; he exclaims “What means this shouting? I do fear the people / Choose Caesar for their king” (1.2.84-5), and later in the same scene, he says of Caesar, “Brutus had rather be a villager / Than to repute himself a son of Rome / Under these hard conditions as this time / Is like to lay upon us” (178-81).
Cassius recognizes Brutus’s vanity, and he is able to manipulate his friend into joining the somewhat questionable conspiracy by providing him with a large mirror—that of flattery—in which to admire his honorable figure. Cassius soliloquizes, “Well, Brutus, thou art noble; yet I see / Thy honorable mettle may be wrought / From that it is disposed. Therefore it is meet / That noble minds keep ever with their likes; / For who so firm that cannot be seduced?” (1.2.313-17).
Brutus will not admit to himself that his motives are in any way personal; indeed, he is quick to squelch any such idea. He declares that he is not envious of Caesar at 1.2.168-9, and he makes justifications to himself at 2.1.10-12: “For my part, / I know no personal cause to spurn at him, / But for the general.” Even as he dies, he claims, “My heart doth joy that yet in all my life / I found no man but he was true to me” (5.5.38-9). However much he may make this assertion, he has used Caesar’s supposed betrayal of himself and of his fellow Romans as an excuse for the assassination. And if Brutus’s statement is accurate and Caesar has been true to him, he has himself been untrue and his conduct dishonorable to Caesar.
Cassius’s arguments (and Brutus’s assurances at 1.2.178-81) explicitly indicate that if Brutus is subservient to a dishonorable or cowardly man (as Cassius deems Caesar to be), he is himself dishonored: “He doth bestride the narrow world / Like a Colossus, and we petty men / Walk under his huge legs and peep about / To find ourselves dishonorable graves (1.2.141-44). This is, of course, the best persuasion Cassius could use; according to this argument, Brutus must join the conspiracy if he is to maintain his honor.
Unfortunately for Cassius, however, Brutus is not so malleable that he will passively take orders from the other assassins. After he joins their ranks, Brutus actually starts to manipulate Cassius with his misguided honor, asserting himself and forcing his honorable—but bad—advice upon Cassius. As a result, Antony is left alive and is allowed to speak to the mob after Caesar's death, and the conspirators lose the decisive battle against Octavius and Antony.
In Norman Council’s words, “Ambition . . . is the most enticing vice to which the honorable man is subject” (20). Brutus’s pride in his honor, his ambition to be honorable, is the weakness that leads to his downfall and to the defeat of the conspirators.