For section four, Vendler sees the blackbird as "the inevitable intrusion of consciousness" into the "erotic physical union" presented in the first line of the section (11).
As McNamara states in his critical analyses of section four, "If it is valid to say that 'A man and a woman/ Are one,' that together they form the natural unit of humanity, then it is true in a more comprehensive sense that all existent things ('A man and a woman and a blackbird') are one in the order of nature." From this, McNamara sees the blackbird as an example of the things surrounding man that, by understanding which, he may understand himself more fully (447).
Lewis notes that section four is an abstraction, which is uncharacteristic of Wallace Stevens, "whose poetics are explicitly opposed" to such. Despite its lack of any concrete imagery, this section retains its link to Imagism. "According to Pound, an image needn't be seen, only felt," writes Lewis. "An image is defined not by its appearance, but by the fact that, as poetic expression, it is irreducible" (Lewis, 69).