How we cite our quotes:
I am invisible, understand, simply because people refuse to see me. (Prologue.1)
This suggests that people are capable of seeing the narrator, but that they choose not to.
Or again, you often doubt if you really exist. You wonder whether you aren't simply a phantom in other people's minds. Say, a figure in a nightmare which the sleeper tries with all his strength to destroy. It's when you feel like this that, out of resentment, you begin to bump people back. And, let me confess, you feel that way most of the time. You ache with the need to convince yourself that you do exist in the real world, that you're a part of all the sound and anguish, and you strike out with your fists, you curse and you swear to make them recognize you. And, alas, it's seldom successful. (Prologue.2)
A large part of one's identity is shaped by others' perceptions – without others' perceptions of who he is, the narrator feels lost.
I am not complaining, nor am I protesting either. It is sometimes advantageous to be unseen, although it is most often rather wearing on the nerves. (Prologue.2)
The narrator confesses that there are advantages to being invisible, a sentiment that lines up well with the double-consciousness of W.E.B. DuBois. Still, being invisible is most often very frustrating.