Pritzker Prize
Martin being a Pritzker Architecture Prize winner and chosen as the architect for designing a multi-billion dollar city is an allegory with deeper meaning. The allegory is that Martin is given the keys to design a city, but he himself is breaking the natural design of sexual intimacy by having sex with an animal. Thus, provoking the question from Albee as to how this will effect the design of an entire city.
Ross
Ross and his friendship with Martin is an allegory for media in our current society. Ross writes a letter to Stevie in order to tell her of Martin's bestiality, and to protect the television station from Martin's interview airing. We see that Ross is heavily invested in protecting the "news," but where is his protection of his friend, and getting him the help he needs? We see the corrupt nature of the media to hold on to their power of influence at the cost of relationships and judging others if they don't fit the mold they need them to be in.
Who is Sylvia?
The play itself is an allegory for what would occur if someone didn't abide by the taboos created in society. Albee plays out the drama in Martin and Stevie's home, but the implication is that it would have a much wider effect on society.
Stevie and the Goat
Stevie slits the throat of the goat that Martin is in love with. This is a symbol of the fact that she is willing to go to even greater lengths than Martin could have imagined in order to keep her love with her husband. More analytically, this act represents the aversion of society towards sexual taboos like bestiality. Stevie, representative of society and its norms, effectively closes down all possibilities of Martin's indulgence in his deviancy through force, reinforcing societal rules.
What not Whom
Martin refers to Sylvia as "her" and "whom" throughout the play, and Stevie despises this, as it is a symbol of him making an animal human. He's taking what is unnatural and making it natural while Stevie is specific to stop this kind of language from becoming normal.
The Big Fight and Billy's Vase
In the scene where Stevie finds out about Martin's affair and confronts him, the two argue, and in the process of their argument Stevie destroys many items in the room. The destruction of the living room, which is a physical representation of their seemingly well-put-together family, symbolizes the deterioration of their family unit. During this scene, Billy also returns in order to move a vase he made for his parents out of the way of destruction, indicating his attempts to preserve a portion of his family and his relationships with his parents from the destruction he knows is occurring--it is a reminder to Stevie and Martin that their actions not only affect them, but their son.
Sylvia: The Goat
Sylvia is, of course, a symbol of Martin's sexual deviancy. More than this, she is a goat, an animal which is commonly seen as a symbol of sexual interactions and fertility, emphasizing the animalistic nature of Martin's 'affair.' Sylvia is also a representation of a deeper argument that Albee is making about sexual taboos, one concerning homosexuality and the so-called 'slippery slope.' Essentially, the slippery-slope argument states that homosexual behavior leads to deviant sexual behavior, like bestiality. Part of the reason why Albee has Martin have an affair with a goat is to illustrate how outlandish this argument is, by demonstrating how very different it is for a person to love someone of the same gender, and a person to love someone of a different species.
Ross's Letter
Ross chooses to reveal Martin's affair to Stevie through a letter, rather than in a more personal means of contact. This choice, and the letter itself, both represent a kind of distanced approach to human relationships which is depicted throughout the play. Additionally, the letter indicates a return to traditionalism which runs contrary to Martin's decisions to engage in bestiality, cementing Ross's place as a fervent opponent of his deviancy.