Nearly a month after his grand realization in prison, Yank is released and goes to the local I.W.W. chapter on the waterfront to join. Despite what we and Yank have heard about the fearsome Wobblies from the senator's speech, this general assembly room and reading room are very commonplace. Yank, who has approached the door with a visible sense of mystery and trepidation, is disbelieving when he sees how normal everything looks inside with the longshoremen, other workers, and the secretary.
When the secretary asks him what he is there for, he tells them he has come to join the organization. Hearing that he is a fireman gives particular satisfaction to the secretary, who mentions that the IWW has not had as much success recruiting firemen as longshoremen. He asks Yank his name to make out a membership card; it is Robert Smith. The secretary then shows Yank various pamphlets the organization has put together and asks him to pass them out on his ship to try to win over some of the other firemen.
Yank seems confused, however, since he had come seeking a violent group. The more he insinuates this in his conversation with the secretary, the more suspicious and cold the latter becomes, until at last he concludes from Yank's plan to dynamite the Douglas Steel Trust that Yank must be a police agent or police-paid worker trying to provoke him into saying something incriminating. The secretary has the other Wobblies throw Yank out.
Out on the street, Yank rants against the Wobblies as part of the whole socialist and Salvation Army political claptrap he had heard from Long. He looks up at the moon and bemoans his feeling of impotence and blindness in the world. A policeman comes and forces him to get up and get on his way.
The next day at twilight, Yank goes to the monkey house at the zoo, intending to see a real ape for himself after having been “called” one by Mildred. He waits until late in the day so that he can confront the impressive gorilla alone. Speaking to the great ape who stands alone in his cage staring back at him, Yank marvels at the his strength and wonders about how dominant the gorilla must be among the other monkeys, whose noisy screeching and chatter dies down almost in deference to the gorilla.
Yank begins to see himself in the gorilla: powerful, but alienated, lonely, and caged. Even more so, he realizes that they both are mocked; other people are afraid of their power but willing to gape at them when they are behind bars. Yank addresses the gorilla with alternating tones of voice, from deep sympathy to a kind of friendly derision; the gorilla seems to respond to him.
Yank tells the gorilla that he had seen the dawn that morning and finally felt the beauty of the world that Paddy had described; nevertheless, he feels that he does not “belong” to such a life because he has lived no past with it. Likewise, he does not belong to most of society. He thinks he can reverse this line of thinking by claiming that it is rather society that does not belong to him; but in the end he has had enough of thinking.
Calling the gorilla “brother,” Yank opens its cage and extends his hand for a handshake. However, the gorilla crushes him and throws him into the cage. Yank drags himself up and begins a mock circus barker's speech calling attention to himself sarcastically as the “Hairy Ape” on exhibition.
The last two scenes of the play see Yank in a sense betrayed twice by groups and people he thinks he belongs to: the Wobblies and the gorilla. If Mildred's look of horror inflicted upon him the trauma and shame that would drive him towards violent action, it is these twin traumas that finally kill him. We may even imagine that had the gorilla found some way to insult Yank without crushing him to death, Yank would have killed himself out of utter despair.
These two scenes, even though they seem so congruent with the rest of the oppressive and manic mood of the play (and O'Neill's style in general), actually represent a second decisive turning point. Mildred's encounter proposes the problem to Yank that there might be an upper-class, or general societal, disdain for him that is even more powerful than his disdain for them. However, in the logic of drama, this proposes the simple solution of revenge—a straightforward tit-for-tat—which is exactly what Yank plans to do originally, first with Mildred personally and then with her father's steelworks. What Yank comes to realize, however, is that both Mildred and the steelworks only represent symbols of a society from which he is alienated, whose power is infinitely greater than his. Reduced to impotence, his only option is to destroy himself.
So long as he felt himself in possession of the kind of power and self-confidence that suggested that he could effect material change in his life on his own, Yank could take as many police beatings and hosings as could be given him, without breaking. It is the creeping doubt that breaks him both emotionally and physically. We can imagine another ending to the play, which might in fact seem like the more conventional way of ending the drama: Yank manages to get his hands on dynamite (for example, the I.W.W. might turn out to be the sympathetic, violent gang he had expected them to be) and successfully blows up the steelworks. The play could end there, with Yank restored to the feeling of power and masculine dominance he had in the first scene; but this conclusion would not have as much aesthetic merit and emotional truth as a play. Indeed, it would literally be Yank's fantasy, and though explosions might bring some entertainment value to the play, it would not shock and move the audience in a deeper emotional and cognitive sense. Aristotle in his discussion of tragic drama in Poetics makes exactly such a distinction: given that a goal of tragedy is to arouse powerful emotions in the audience, either the plot or stage effects can be used to achieve impact. However, the former is elevated far above the latter.
Thus, instead of exploding steelworks and maybe even hand-to-hand combat with Yank tossing Pinkerton agents through the air, we get his lengthy and complex monologue cum dialogue with the gorilla. We should find this monologue all the more incredible for how unusual it is for Yank to speak at such length, trying to both sustain and develop a thought as complex as trying to figure out his place in the world. Paddy is able to go on at length because of a kind of elegiac impulse and Long because of his socialist doctrine; but Yank, directly opposed to them during all the times he talked them down, is more embodied in his brawn than his words.
To say that Yank is just inarticulate and uneducated, however, would do his character a great injustice. O'Neill presents him to us in all the unfamiliar disorder, passion, and disdain of an almost alien class, but also crucially invests Yank with a kind of humanity that no other character in the play possesses. Even Paddy is more or less fixed in his worldview, admirable as it may be.
We get the sense that O'Neill, in tight control of his freewheeling protagonist, knows the reason for the latter's suffering and inability to form a coherent view of life; but it becomes a highly difficult problem to present this knowledge through characters. Without a classical deus ex machina, the only options would be Yank or another character. If Yank, then it would contradict his disdain for thinking and any kind of reasoning more complex than straightforward action and confidence, as he displayed in the first scene; if other characters, then Yank would probably mock them as he did Paddy and Long, or else if he listened to them, they would gain authority over him. O'Neill solves this riddle by means of extended time: from Scene Four just after his encounter with Mildred through his time in prison and when thrown out from the I.W.W. meeting, Yank is in a sense more physically oppressed by thinking than by all the beatings he gets. This weight is manifested in his “Thinker” pose, which, as the crux of Rodin's monumental “Gates of Hell” suggests the crucial position of Yank in the fallen world of capitalistic America.
As a concluding note, we may recall the final words of Paddy's long address to Yank, in which he (Paddy) mourned the mechanization and dehumanization of ship labor:
Is it one wid this you'd be, Yank—black smoke from the funnels smudging the sea, smudging the decks—the bloody engines pounding and throbbing and shaking wid divil a sight of sun or a breath of clean air—choking our lungs wid coal dust—breaking our backs and hearts in the hell of the stokehole—feeding the bloody furnace—feeding our lives along wid the coal, I'm thinking-caged in by steel from a sight of the sky like bloody apes in the Zoo! (With a harsh laugh) Ho-ho; divil mend you! Is it to belong to that you're wishing? Is it a flesh and blood wheel of the engines you'd be? (46-7)
In Scene One, when Paddy says this, it seems to be an actual question: Yank could choose to be one way or another. However, by the end of the play, we come to realize along with Yank, who says as much explicitly, that although Paddy was right that modern labor is inhuman and the machine puts man in chains rather than empowering him, Yank has no alternative life because he has no past other than laboring as part of this machine.