In Act 1, Scene 2, Cassius is holding a long conversation with Brutus. Cassius is trying to organize a conspiracy to assassinate Julius Caesar before Caesar can be made king by the Roman Senate. Brutus is a good friend of Julius Caesar, and at this point he is not susceptible to being drawn into a plot against his friend. Cassius is slowly and insidiously feeling Brutus out while trying to change his opinion of Caesar. Brutus gives Cassius a clue as to how he can be manipulated when he tells him:
But wherefore do you hold me here so long?
What is it that you would impart to me?
If it be aught toward the general good,
Set honor in one eye and death i' the other
And I will look on both indifferently.
For let the gods so speed me as I love
The name of honor more than I fear death.
Cassius realizes that the way to influence Brutus is to appeal to his sense of duty and honor. Cassius himself is a different type of person. He is not concerned about honor but about his own personal welfare and security. He is afraid that if Caesar becomes king he will turn into a demagogue and a tyrant. The rich and powerful Romans will probably suffer because Caesar will impose taxes on them and interfere with their privileges. Cassius is probably even afraid for his life. He knows that Caesar dislikes and distrusts him. He also knows that Caesar has no qualms about killing people who get in his way. Plutarch writes that Julius Caesar was responsible for the deaths of about two million people during his lifetime.
After Brutus leaves him, Cassius speaks his mind in a revealing soliloquy.
Caesar doth bear me hard, but he loves Brutus.
If I were Brutus now and he were Cassius,
He should not humor me. I will this night,
In several hands, in at his windows throw,
As if they came from several citizens,
Writings, all tending to the great opinion
That Rome holds of his name, wherein obscurely
Caesar's ambition shall be glanced at.
And after this let Caesar seat him sure;
For we will shake him, or worse days endure.
Cassius will appeal to Brutus' sense of honor, although Cassius has no such sense himself. Cassius is very cunning, whereas Brutus is very open and honest. Shakespeare has shown in other plays that cunning people like Cassius have an advantage over honest people like Brutus. For instance, the cunning villain Edmund in Shakespeare's King Lear is able to turn his father against Edgar, Edmund's half-brother, and then obtain his father's title of Earl of Gloucester with all his properties by betraying him to the Duke of Cornwall and Cornwall's wife Regan. Edmund congratulates himself in private when he says:
A credulous father! and a brother noble,
Whose nature is so far from doing harms
That he suspects none: on whose foolish honesty
My practices ride easy!
Iago in Shakespeare's Othello finds it easy to "practice" on both Cassio and Othello because they are honest and honorable and assume that other people are like themselves.