Quote 16
CASSIUS
Men at some time are masters of their fates.
The fault, dear Brutus, is not in our stars,
But in ourselves that we are underlings.
'Brutus' and 'Caesar'—what should be in that
'Caesar'?
Why should that name be sounded more than
yours?
Write them together, yours is as fair a name;
Sound them, it doth become the mouth as well;
Weigh them, it is as heavy; conjure with 'em,
'Brutus' will start a spirit as soon as 'Caesar.' (1.2.146-156)
Cassius seems to think that by playing on his desire for personal glory, he can sway Brutus to join the conspirators. The thing is, we're not sure if Brutus is interested in self-gain. It seems Cassius keeps bringing up personal gain because it's <em>his</em> motivation for taking down Caesar.
Quote 17
CASSIUS
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? (1.2.320-324)
Even though Cassius thinks Brutus is a "noble" guy, he also thinks that just about anyone, including Brutus, can be manipulated or "seduced."
Quote 18
CASSIUS
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 glancèd at
And after this, let Caesar seat him sure,
For we will shake him, or worse days endure. (1.2.327-334)
Cassius hopes that by planting fake letters from "citizens" urging Brutus to lead Rome, Brutus will be convinced to join the conspiracy against Julius Caesar.