You could almost imagine the title on the banner of a lifestyle magazine; "Eight Things that Will Drive Him Crazy," "Ten Fitness Tips for the New Year," "Thirteen Ways of Looking at a Blackbird!" In terms of content, of course, there's no similarity, and, as far as we know, magazine headlines looked different in Stevens's day. But this kind of title has the same purpose every time: to be as clear and direct as possible about what you'll find if you "look inside." Without this title, we might be confused about how the sections of the poem are supposed to fit together. The poem is odd enough without an odd title, to boot.