“Passage to India” is a salute to the idea of the evolutionary progress of the human race; it celebrates the scientific achievements of the age, looks forward to the imminent dawning of an era in which all divisions and separations between people, and people and nature, will be eliminated, and heralds the spiritual voyage of every human soul into the depths of the inner universe. Whitman himself described the meaning of his poem, saying “that the divine efforts of heroes, and their ideas . . . will finally prevail, and be accomplished, however long deferred.”

The poem begins by celebrating three achievements of contemporary technology: the opening of the Suez Canal in 1869, the laying of the trans-Atlantic cable, and the growth of the American transcontinental railroad. These achievements outshine the Seven Wonders of the Ancient World; however, the poet still hears the call of the ancient past, embodied in the myths and fables of Asia, with their daring reach toward an unfathomable spiritual truth. The refrain “Passage to India” therefore suggests the theme of inner as well as outer exploration.

Section 3 elaborates on two of the new wonders, picturing the opening ceremony of the Suez Canal and the grand landscapes through which the American railroad passes. The poet has been careful to establish that the great works of the present should be celebrated not merely for the human skill and knowledge to which they testify but also because they mark an important stage in the fulfillment of the divine plan: the human race coming together in unity. The section ends by flashing back to the past and invoking the name of Christopher Columbus. Whitman liked to present himself as an idealized Columbus figure, exploring new literary and psychic worlds, yet rejected by his countrymen. Perhaps he had in mind Thoreau’s injunction in the conclusion to Walden (1854): “[B]e Columbus to whole new continents and worlds within you, opening new channels, not of trade, but of thought.”

Section 5 is central to the poem because it conveys Whitman’s vision of the role of the poet in human evolution. Whitman first stretches the reader’s awareness by evoking the vast earth “swimming in space/ Cover’d all over with visible power and beauty.” He then describes the troubled history of the human race; the myriad restless, dissatisfied, questing lives. He alludes to the Transcendentalist idea that humankind and nature have become separated. No connection is perceived between the human, feeling subject and the apparently unresponsive external world: “What is this earth to our affections? (unloving earth, without a throb to answer ours . . . ).” Yet the divine plan remains and shall be achieved, with the help of the poet, who is the “true son of God.”

Coming after the inventors and the scientists, the poet will justify them (a deliberate echo of seventeenth century English poet John Milton, who wrote that he sought to justify the ways of God to humankind) by fully humanizing a mechanized world: He will soothe hearts, open all secrets, and join nature and humans in unity. Whitman thus reiterates the poetic manifesto contained in the preface to the 1855 edition of Leaves of Grass: “Folks expect of the poet more than the beauty and dignity which always attach to dumb real objects . . . they expect him to indicate the path between reality and their souls.”

After section 6 has presented a panorama of some of the great events in human history and again invoked Columbus, section 7 develops the theme implicit earlier in the poem, of the poet as spiritual explorer. This theme carries the poem through to its conclusion. The poet must journey, in partnership with his soul, to “primal thought,” beyond all limitations of the physical body, to the infinite regions of the cosmic mind. The restless desire to expand, to voyage on the ocean of Being, becomes more and more urgent in the final section of the poem. The poet and his soul have lingered long enough. Now is the time to be bold and reckless, for the cosmic seas are safe: “[A]re they not all the seas of God?”