The opening line of Eliot's poem is an exercise of figurative language, seeking to articulate what might or should be in a context hopelessly locked into what actually is. The implications of "Let us go then, you and I," is a reminder as the poem develops that the narrator lives in a world of alienating loneliness and isolation as opposed to unity. The image of being "spread out against the evening sky" is breathtaking in its coherency, until it becomes evident that there is only isolation within the speaker's world. Society is described in an idealistic construct, undercut with what is actually experienced.
The speaker's inability to bridge the world of what is and what might be haunts Prufrock and the reader. This can be seen in the meter of specific lines. For example, "In the room the women come and go/ Talking of Michelangelo" is a line that links rhyme and meter with a superficial and transitory condition of being. The world that "spreads out" to the narrator is one where lightness and the transitory can be seen. This world is one where both how higher elements of "culture" are simply exchanged with no real and substantive meaning. Even the manner of speaking where the inauthentic "come and go" seems to merge with "Michelangelo" is reflective of this condition of being. Society is shown in a superficial light, in contrast to the gravity with which the speaker appropriates the world and his disjointed place in it.
The descent which is intrinsic to the poem's epigraph can be seen in the structure of the stanzas. Stanza one presents a conditional view of the world, an almost hopeful image of what can be, only to be undercut by the women in stanza two. There is a polluted condition of the world in the third stanza of the poem. The pollution of the world around the speaker is evident, something conveyed through the poem's structure:
The yellow fog that rubs its back upon the window-panes,The yellow smoke that rubs its muzzle on the window-panes,Licked its tongue into the corners of the evening,Lingered upon the pools that stand in drains,Let fall upon its back the soot that falls from chimneys,
The Love Song of J. Alfred Prufrock does much to describe not only society at the time it was written, but it can also be applied to today's world. T.S. Eliot wrote and published this piece around 1915. Around that time, especially in America, many changes were taking place. The Roaring Twenties were just around the corner, new inventions were taking place, life was good. However, this wasn't always the case. Often called the first Modernist poem,“Prufrock” captures the emptiness and alienation many people experienced while living
in impersonal modern cities, such as New York. This piece as a whole is describes the alienation, and I believe it to be the most important part as well.
Hope this helps!