From which Shakespearean play (act and scene if possible) comes the Quote
"Who is Sylvia"?

"Who is Silvia?" is from William Shakespeare's "The Two Gentlemen of
Verona," Act IV, Scene II.

Who is Silvia? what is she,
That all our swains commend her? 
Holy, fair and wise is she; 
The heaven such grace did lend her, 
That she might admired be. 
Is she kind as she is fair? 
For beauty lives with kindness. 
Love doth to her eyes repair, 
To help him of his blindness, 
And, being help'd, inhabits there. 
Then to Silvia let us sing, 
That Silvia is excelling; 
She excels each mortal thing 
Upon the dull earth dwelling: 
To her let us garlands bring. 

About Shakespeare: The Two Gentlemen of Verona
http://shakespeare.about.com/library/bltwo_4_2.htm

Google Web Search: shakespeare "who is silvia"
://www.google.com/search?hl=en&q=shakespeare+%22who+is+silvia%22

I am confident that this is precisely the information you seek. If it
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clarification; I'll gladly offer further assistance before you rate my
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Best regards,
pinkfreud

Wow!    I only joined 20 minutes ago, and already have my first
answer.  Thank you very much, pinkfreud.  I guess this was a pretty
easy one for you but much appreciated anyway.

Thank you for the five stars and the nice tip!

~pinkfreud

This text has been set to music about a zillion times -- or maybe you
know that and that's why you're looking for the source?  Some of the
best are by Gerald Finzi, Roger Quilter and of course Schubert's "An
Sylvie."

Thanks gregg65.ga.      Not sure whether you are a punter like me, or
a researcher.    I didn't know about the music, though I am not
surprised and will look into it, to continue my education!   The
question came up quite randomly at a party........   Did you know that
Edward Albee's controversial play, "The Goat" (which was on in London
last year)is subtitled "Who is Sylvia"!  Sylvia was actually a goat
and she met with an untimely end.  I won't spoil it for you, in case
you decide to see it one day.