The first section of this poem contains the purpose of the overall poem. Whitman declares that he writes this poem as a form of celebration of his own being. It then quickly becomes obvious, however, that he is celebrating all of humanity, not just himself. He says that we are to believe whatever he tells us and that we need to take on the various roles that he is going to assume in this poem. He states his belief in a common humanity because we all share the same atoms that make up life.
Whitman then describes how he and his soul, who takes the form of another character separate from Whitman himself, look at nature together and in particular contemplate a blade of grass. He ends up by saying that he is determined to speak out in spite of "creeds and schools" that may counsel him to keep quiet. He wants to express his "original energy."