The song in the poem is what provides the internal reflection for the subjective experience that is so vital to the poem. The speaker, presumably Wordsworth, experiences what he does because of the song. He sees the woman working in the field. By itself, this might be an experience in its own right, but it is the song she sings that becomes the trigger for the speaker's moral and artistic imagination. The words in the song are not entirely clear to the speaker and this lexical ambiguity is critically important. It is through this that Wordsworth is able to project what he thinks the song means. The song is the vehicle that takes Wordsworth's imagination to different parts of the world and it allows him to envision the sadness or the "melancholy strain" that he perceives to be present. It is the song that allows for the subjective experience. Only through the song is Wordsworth is able to grasp the moment of the woman singing. The notions of "seeing into the life of things" and that poetry is rooted in the common experiences comes from the song being sung in the poem.