The stance that Wallace Stevens is making on humanity and nature in this poem is that everything that is currently existent on the earth is somehow, at some level, interconnected. When the woman sings not only is her song derivative of the sea, but the sea is also a derivative of her song and what she is. Influenced by the sea, the singer learns to vocalize and deliver her message in a certain fashion, but without the song of the woman, the sea has no meaning either. If the woman never sings, in what way do we understand the sea? The sea certainly cannot sound like the singing woman if there was no song to begin with, and vice versa—almost a “chicken or the egg?” complex. That sort of interconnection is the take I gathered on Stevens’ poem. If not for consideration of all the earth’s possessions, both humanity and nature would cease to exist in the way we know them.