Be not deceived: if I have veil'd my look,
I turn the trouble of my countenance
Merely upon myself. Vexed I am
Of late with passions of some difference,
Conceptions only proper to myself,
Which give some soil perhaps to my behaviors;
But let not therefore my good friends be grieved--
Among which number, Cassius, be you one--
Nor construe any further my neglect,
Than that poor Brutus, with himself at war,
Forgets the shows of love to other men.
Then, Brutus, I have much mistook your passion;
By means whereof this breast of mine hath buried
Thoughts of great value, worthy cogitations.
Tell me, good Brutus, can you see your face?
No, Cassius; for the eye sees not itself,
But by reflection, by some other things.
(Julius Caesar, Act I, Scene II)