Proteus is a young nobleman from Verona. He's supposed to be Valentine's best friend and Julia's sweetie, but after he falls for Valentine's girlfriend, he stabs his BFF in the back and tries to rape Silvia. When he's confronted, he undergoes a sudden and miraculous transformation, which prompts him to make up with Valentine and fall back in love with Julia.
Like the shape-shifting sea god he shares his name with, Proteus is pretty erratic and changeable, don't you think? He falls in and out of love (with women and his best friend) as often as some people change clothes, and he's also pretty crafty and deceptive. He has no trouble being two-faced as he betrays his best friend and he lies to just about everyone he knows.
OK, Proteus sounds like a pretty bad guy. So why is his horrible behavior forgiven at the play's end? Well, we're not quite sure – the sequence of events in the final scene is pretty bizarre. Still, we can try to understand why Valentine and Julia forgive Proteus by thinking about the play's themes of male friendship and transformation.
First things first. Let's think about the importance of male friendship in the play. At the beginning of Two Gentlemen, Proteus and Valentine are best buds. Check out how sweet Proteus is when Valentine sets out for Milan: "Wilt thou be gone? Sweet Valentine, adieu!/ Think on thy Proteus" when you're away (1.1.1). It's pretty clear that Valentine also feels the same way about his BFF. When the Duke of Milan asks about Proteus's character, Valentine says, "I know him as myself; for from our infancy/ We have conversed and spent our hours together" (2.4.20). According to Valentine, the guys have known each other since they were babies and have spent their entire lives together. When Proteus says, "I know him as myself," he means to suggest that he knows Proteus as well as he knows himself. At the same time, the phrase "I know him as myself" also suggests that Proteus and Valentine are like two halves of the same being.
This idea echoes a common sixteenth-century idea made famous by Thomas Elyot's The Book Named the Governor. In Book 2, Chapter 11, Elyot says that friendship makes "two persons one in having and suffering. And therefore a friend is properly named of philosophers the other I. For that in them is but one mind and one possession" (2.11). In Shakespeare's day, male friendship was considered one of the most sacred and important bonds.
So, when Valentine catches Proteus trying to rape Silvia, Valentine is outraged that his friend would betray him. For Valentine, Proteus's violation of Silvia is less important than Proteus's violation of the bonds of friendship. When Proteus apologizes, he says he's sorry for being a bad friend, not for the attempted rape:
My shame and guilt confounds me.
Forgive me, Valentine: if hearty sorrow
Be a sufficient ransom for offence,
I tender 't here; I do as truly suffer
As e'er I did commit. (5.4.4)
Proteus never expresses remorse for his crime against Silvia. He feels bad because he hurt Valentine's feelings and betrayed his friend's trust. When Valentine forgives him without a lot of fuss, the play seems to suggest that mending male friendship is more important than anything else.
OK, so we can begin to understand Valentine's motivation to forgive Proteus, but why does Julia forgive him? There are no easy answers to this question, but, again, we try to understand by taking a close look at the play. Here's what Julia says after Proteus assaults Silvia:
O Proteus, let this habit make thee blush!
Be thou ashamed that I have took upon me
Such an immodest raiment, if shame live
In a disguise of love:
It is the lesser blot, modesty finds,
Women to change their shapes than men their minds. (5.4.7)
Again, there's no mention of Silvia. Julia is irate because 1) she's embarrassed that she had to dress as a boy ("Sebastian") in order to chase down Proteus, and 2) because Proteus has been unfaithful and "change[d]" his mind about loving her. How does Proteus respond to this?
Than men their minds! 'tis true.
O heaven! were man
But constant, he were perfect. (5.4.7)
Here, Proteus suddenly realizes that Julia is right about his behavior – he's been falling in and out of love and his disloyalty and inconstancy makes him flawed. (Yet, there's still no recognition that his attempt to rape Silvia is problematic.) What's going on here? Literary scholar Marjorie Garber points out that, at this moment in the play, Proteus's true nature is "unmasked" at the exact same time that Julia's true identity has been revealed (Shakespeare After All, 46). The point may be that, while human beings can be fickle, changeable, and unstable, they are also capable of self-revelation and change (for the better). At the same time, the abruptness of Proteus's seeming transformation leaves us skeptical at best.
Check out "What's Up With the Ending?" if you want to think about this some more.