This may prove food to my displeasure. That young start-up hath all the glory of my overthrow. If I can cross him any way, I bless myself every way. (A1,S3)
Don John confesses his hatred for Claudio, admitting that Claudio’s pain brings him happiness. Don John differs from other manipulators like Don Pedro in that his motivations are outright malicious: Don John fully intends to cause hurt and discord, reveling in making trouble for others. Curiously, though, Don John is one of the few characters in the play who is actually honest with himself.
Grow this to what adverse issue it can, I will put it in practice. Be cunning in the working this, and thy fee is a thousand ducats. (A2,S2)
Don John offers a financial reward to his underling for carrying out his shady plans. This transaction shows the coldness of Don John’s existence. While Don Pedro conducts his deceptions jovially with close friends, almost like a hobby, Don John pays off assistants to do his bidding as though he were hiring hitmen.
You may think I love you not. Let that appear hereafter, and aim better at me that I now will manifest. (A3,S2)
Here, after making Claudio believe the worst about Hero, Don John cruelly convinces Claudio that he’s acting in the young man’s best interests. Don John disguises his poisonous deceit by pretending to be Claudio’s truest friend, the only one who cares enough about Claudio to tell him the hard truth. This act works like a charm on the impressionable Claudio, revealing the depth of Don John’s skill at manipulation.
There is not chastity enough in language, Without offense, to utter them.—Thus, pretty lady, I am sorry for thy much misgovernment. (A4,S1)
Here, Don John joins the chorus of voices shaming Hero for infidelity, despite knowing full well that she is innocent. The heartless Don John is happy to let misfortune fall on the innocent Hero, as long as he gets what he wants: strife for the “friends” he resents. Don John likely wouldn’t care even if Hero had actually been unfaithful.
Think not on him till tomorrow. I’ll devise thee brave punishments for him.—Strike up, pipers. (A5,S4)
After multiple romantic matches have come together, Benedick declares that no one should worry about Don John and commands everyone to dance. For all the hurt he caused, Don John is still such an outsider that he is easily ignored by all the others as they celebrate. This easy erasure of his presence shows the consequences of living a life devoid of human connection, devoted to harming others.