OK, so Whitman's poem is hardly the first example of this age-old comparison, perhaps most famously used in Shakespeare's "All the world's a stage" speech. But the speaker of the poem adds a unique twist, suggesting that the roles we play in life are more enduring than we are.
- Line 3: The everyday clothes that the passengers wear into the city are compared to theatrical "costumes" using metaphor.
- Lines 86-88: The speaker uses subtle irony in these lines. Usually, an actor or actress looks back on a part they once played, but here, it's the role that looks back on the actor. In this extended metaphor between acting and everyday life, it doesn't matter whether the role one plays is big or small.
- Lines 121-122: The speaker repeats the metaphor, comparing life to theatre, but he suggests that people have the power to make their role "great or small."
- Line 147: The word "parts" forms a pun. He means "parts of a whole" and also "parts" in the sense of a theatrical role. He uses the same phrase, "great or small" to describe the role that these parts can play. He seems to give equal value to both the great and the small.