Lines 87-131 Summary:
Prufrock wonders if, after various social gestures, it would have been worthwhile to act decisively if it resulted in a woman's rejection of him. He thinks he is not a Prince Hamlet figure, but a secondary character in life. Worried over growing old, he adopts the fashions of youth. By the beach, he sees images of mermaids singing and swimming.
The movement in the final section of the poem swings from fairly concrete, realistic scenes from the social world - "After the cups, the marmalade, the teaAfter the novels, and the teacups, after the skirts that trail along the floor" (88, 102) - to fantastic images of mermaids "riding seaward on the waves / Combing the white hair of the waves blown back" (126-127). Eliot's objective correlative grows more vague; what exactly does Prufrock feel here? Perhaps Prufrock himself is unsure: "It is impossible to say just what I mean! / But as if a magic lantern threw the nerves in patterns on a screen" (104-105). His own inarticulacy results in the magic lantern's wild kaleidoscopic imagery of teacups and mermaids; aside from desperation and loneliness, confusion is one of the objective correlative's main emotional associations.
But Prufrock shows a wise self-regard when he admits he is
not Prince Hamlet, nor was meant to be;
Am an attendant lord, one that will do
To swell a progress, start a scene or two,
Advise the prince; no doubt, an easy tool,
Deferential, glad to be of use,
Politic, cautious, and meticulous;
Hamlet, Shakespeare's famous tragic hero from the play of the same name, is literature's other great indecisive man. Hamlet waffles between wanting to kill his stepfather and holding off for a variety of reasons. The allusion, then, is somewhat ironic, since Prufrock is not even as decisive as Hamlet is. Instead, he is more like the doddering Polonius of Hamlet (the "for you yourself, sir" quote from Hamlet 2.2.205-206, if the "ragged claws"  line alludes to it, is spoken by Hamlet to Polonius), or the conventional Shakespearean "Fool" (119). Prufrock is the second-in-command at best, and he comes off as a mock-hero; even the absence of an "I" preceding "Am an attendant lord" bespeaks his lack of ego. The numerous caesurae (pauses) from commas and semicolons in the stanza underscore Prufrock's stagnation and paralysis.
The only thing in Prufrock's life not paralyzed is time; it marches on, and Prufrock laments "I grow old . . . I grow old . . . / I shall wear the bottoms of my trousers rolled" (121). The rolled trouser, a popular bohemian style at the time, is a pathetic attempt to ward off death. While he continues to be anxious about the future, Prufrock now seems to regard the future, paradoxically, from a future standpoint. His refrain of "And would it have been worth it, after all" (87, 99) places his actions in the perfect conditional tense. It is as though he is reviewing actions he has yet to take. Either time has accelerated his aging process, or this look to the past is a way for Prufrock to delude himself into thinking he has made some decisive progress in life.
Previously, Prufrock wondered if he should "dare / Disturb the universe" (45-46) and squeeze "the universe into a ball" (92). The latter is a reference to Marvell's "To His Coy Mistress": "Let us roll all our strength and all / Our sweetness up into one ball, / And tear our pleasures with rough strife / Thorough the iron gates of life" (41-44). Marvell urges his lady to engage in sex with him, as death draws ever closer and their time is running out.
Prufrock, on the other hand, knows he is going to die soon but he still cannot even "dare to eat a peach" (122). While Eliot's main intent is to trivialize Prufrock's anxieties - a simple piece of fruit confounds him - the peach has a few other possible meanings. First, it is the Chinese symbol for marriage and immortality, two things Prufrock desires. Moreover, the peach, through shape and texture, has long been a symbol for female genitalia. Prufrock's anxiety about eating a peach, then, has much to do with his feelings of sexual inadequacy, his worry that his balding head and thin physique earn him the scorn of women.
Accordingly, Prufrock immediately switches his attention to the mermaids "singing, each to each" (124) - the society of women who ignore him. The elusive images perhaps have more cohesion than on first glance:
I have seen them riding seaward on the waves
Combing the white hair of the waves blown back
When the wind blows the water white and black.
Prufrock has just wondered "Shall I part my hair behind?" (122), and previously he has agonized over his bald spot, turned his keen eye to the women's arms "downed with light brown hair!" (64), and agonized over eating a fuzzy peach. Mermaids are conventionally depicted combing their hair with a mirror, so as symbols of vanity and lush beauty - "wreathed with seaweed red and brown" (130), they possess even more artificial hair - they threaten Prufrock (whose thinning hair is perhaps now a salt-and-pepper mixture of "white and black" and no longer "red and brown").
When Prufrock finishes the poem by pronouncing "We have lingered in the chambers of the seaTill human voices wake us, and we drown" (129, 131), he completes the vertical descent Eliot has been deploying throughout the poem. He has plunged into his own Dantesque underworld and, through the "We" pronoun, forces us to accompany him - hoping, like da Montefeltro from the epigraph, that we will not be able to return to the mermaids on top and shame him by repeating his story.
The concluding two three-line stanzas act as a sestet (six lines). Although the rhyme scheme differs (here it is abbcdd), Petrarchan sonnets complement the opening octet (first eight lines) with a sestet. This is Eliot's final mock-allusion to yet another Renaissance artist (after Dante and Michelangelo). Petrarch unrequitedly mooned after his love, Laura, but Prufrock, whose name sounds much like Petrarch's, does not even have an unattainable ideal love. He has unattainable, frustrated, paralyzed desire for all women who reject him; they are all inaccessible, and any reminder of the social world ("human voices") drowns him - and, he hopes, his reader-as-Dante - deeper in his watery Hell.