Quote 19
CASSIUS
Stoop then, and wash.
[They smear their hands and swords with Caesar’s blood.]
How many ages hence
Shall this our lofty scene be acted over
In states unborn and accents yet unknown!
BRUTUS
How many times shall Caesar bleed in sport,
That now on Pompey's basis lies along
No worthier than the dust!
CASSIUS
So oft as that shall be,
So often shall the knot of us be called
The men that gave their country liberty. (3.1.123-132)
The conspirators believe they'll go down in history for their act, yet they arrogantly (or naively) assume they will be remembered as heroes, not traitors. The glory of being preserved by history is enough of a lure that that's what they dwell on after the murder, second only to having liberated Rome.
Quote 20
CASSIUS
I did not think you could have been so angry.
BRUTUS
O Cassius, I am sick of many griefs.
CASSIUS
Of your philosophy you make no use
If you give place to accidental evils.
BRUTUS
No man bears sorrow better. Portia is dead. (4.3.164-168)
Brutus exercises another type of humility here: stoicism, or the realization that life is a burden that each man has to bear. He figures he might as well bear suffering nobly rather than getting worked up over every little thing, like his wife dying or murdering his best friend.
Quote 21
CASSIUS
Well, honor is the subject of my story.
I cannot tell what you and other men
Think of this life; but, for my single self,
I had as lief not be as live to be
In awe of such a thing as I myself. (1.2.99-103)
Cassius uses the veil of honor to mask his own ambition. His pride will not allow him to be led by a peer. His pride is wounded by the fact that Caesar, whom Cassius sees as no more worthy than him, has assumed the leadership of Rome.