Any ideas, out there?

Avon calling! I think it's around the early part of Act II of Measure for Measure, when Isabella is (despite her initial intentions) pleading with the stern Angelo for the life of her condemmned brother. The whole speech is too long for memory, but I think the key part this refers to goes something like:

".............. Man, proud man,
Dress'd in a little brief authority,
Most ignorant of what he's most assured,
His glassy essence, like an angry ape,
Plays such fantastic tricks before high heaven
As makes the angels weep; who with our spleens
Would all themselves laugh mortal"


I always loved that section of the play, because it shows Shakespeare's mind at work in all its dancing complexity - even down to the fact that punning use of language was, to him, not mere embellishment but a mainspring of his creative process. Early on after Isabella comes on in this scene, she 'thinks aloud' about the quandary she's in over pleading for mercy on behalf of her brother despite a crime she abhors, saying:

"..... the blow of justice
For which I would not plead, but that I must;
For which I must not plead, but that I am
At war twixt will and will not"

The antitheses of these lines shows the wriggling, driving, balancing act of someone's mind at work, trying to resolve a problem 'on the fly' - and the concluding play on his own name is typical of his sheer joy in language for its' own sake!