Character Analysis
Vindice has a central goal that drives his whole life: revenge. He's been seeking vengeance for nine years, and he's a bit like Inigo Montoya in The Princess Bride. Inigo says he's been in the revenge business so long, he doesn't know quite what else to do with himself after he gets it. Of course, in Vindice's case, there will be no after, but he doesn't know that at the beginning.
Despite his fixation, Vindice is still a complicated man, with skills and interests and ideas. He's clever, and he seems to be a good actor—he successfully makes up a character, Piato, to help put his plans into action, and he's able to make up another character for himself later, too. He's witty, thoughtful, and good with words, as his long speeches show, though he gets carried away with philosophy at odd moments. He's not alone in this musing: Lots of revenge tragedy characters pause for a bit of speculation on natural philosophy during tense action scenes. Go figure.
Vindice also has a strong sense of justice and a lot of family loyalty, although it gets expressed in pretty weird ways… like threatening his mother with daggers until she's more supportive of his sister's chastity.
But while we can easily identify good qualities in Vindice, they get so wrapped up in his plans for revenge that we might even say they get twisted. Much like Inigo, Vindice lets revenge drive his whole life. He may not be rehearsing the line, "You killed my father, prepare to die," but he has been carrying his fiancée's skull around for nine years, so it's safe to say that revenge has been running the show for nearly a decade of this dude's life.
Unlike Inigo, Vindice doesn't seem headed for a cheerful post-revenge life on the high seas as the Dread Pirate Roberts. Not surprisingly, Vindice has a grim view of human nature—he's given to bursting out in laments about how sinful humanity is (see: 2.2.147-151), and a lot of his tirades revolve around lust. For instance:
Night! thou that look'st like funeral heralds' fees
Torn down betimes i'th' morning, thou hang'st fittly
To grace those sins that have no grace at all.
Now 'tis full sea abed over the world;
There's juggling of all sides. (2.2.147-151)
Yup, dude thinks pretty much the whole world is boning. While we can see why he's anti-lust—the Duke poisoned his fiancée in a fit of thwarted lust—it all seems a bit extreme. Has Vindice allowed his passion for revenge to corrupt his view of the whole world? It sure seems like it. We definitely don't see him giving anyone the benefit of the doubt in the excerpt above.
There's another question at stake, too: Has Vindice allowed his passion for revenge to corrupt his own character so much that his efforts at justice are twisted? He starts with a passion for revenge against the Duke, who murdered someone close to Vindice. Whether capital punishment is right or not, it's in some sort of proportion to the crime.
But Vindice's desire to kill Lussurioso is less proportionate. Lussurioso is a bad dude and not averse to murder, but he hasn't killed any of Vindice's family or friends—in fact, he doesn't even succeed at seducing Vindice's sister. So why does Vindice think he has a right to kill him? And why is Vindice so gleeful when he's enacting revenge? By the end, Vindice even frames a nobleman for the murder of Lussurioso, which is a capital crime. Where is the sense of justice Vindice started with? We sure can't see it.
Maybe Vindice had a fatal flaw in his character. Maybe he took revenge into his own hands when he should have waited for God or the proper earthly authorities or fate to provide it. Or maybe it's just not possible to stay a good man if revenge is your main goal. The play doesn't say for sure, but it definitely raises the question.
Vindice's Timeline