In what work does Shakespeare say the following: "O thou invisible spirit of wine,"  "if thou hast no name to be known by, let us call thee devil!"  Who is the speaker?

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ladyvols1 eNotes educator| Certified Educator

This quotation comes from Act II Scene III of Othello, Cassio says to Iago:

"I will rather sue to be despised than to deceive so good
a commander with so slight, so drunken, and so indiscreet
an officer. Drunk? and speak parrot? and squabble?
swagger? swear? and discourse fustianwith one's own
shadow? O thou invisible spirit of wine, if thou hast no
name to be known by, let us call thee devil! "

In this paly Iago is evil and constanly stirring up trouble.  At this point in the play Iago is in the act of continuing his plan to ruin Cassio.  He successfully gets Cassio drunk after Othello has told him to stand watch and not celebrate the victory of the war too much.  Iago takes this opportunity to get Cassio drunk, agressive, and fighting with  Roderigo and Montano.  Othello arrives and breaks up the fight.  He inquires as to what is going on and Iago explains that he doesn't really know what caused the fight except that Cassio is drunk and fighting. 

Othello dismisses Cassio.  Iago encourages Cassion to go to Desdemona for intercession on his behalf, while planning to have them caught by Othello.   It is after this that Cassio makes this telling quote about wine.  He is bemoaning his reputation being ruined and is blaming the whole thing on the wine, instead of blaming Iago who has created the situation to begin with.