Needing fast assistance, if you can. I'm referencing quotes I have used in a novel, and cannot find this one in We's text. I hope you can lead me to the right section 'A man is a novel...etc' Many thanks - Glenda Guest

The quote you're looking for is at the top of page 151. It is located on the third page in Record 28 of We by Eugene (Yevgeny) Zamyatin. The edition this quote is from was published by E.P. Dutton in New York. The copyright page notes that the original copyright was obtained in 1924 by E.P. Dutton & Co., Inc.; it was renewed in 1952 by Gregory Zilboorg. 
The section reads:

"What, 'at any moment'?" (But immediately I understood what. The blood rushed to my ears and cheeks.) "Don't speak about that, you must never speak about that! The other I, my former self...but now..."
"How do I know? Man is like a novel: up to the last page one does not know what the end will be. It would not be worth reading otherwise." 
She was stroking my head. I could not see her face, but I could tell by her voice that she was looking somewhere far into the distance; she had hooked herself on to that cloud which was floating silently, slowly, no one know where to.

The conversation is between the narrator, D-503, and I-330. It occurs after he's ordered U- to leave the room. She seems to be saying that the ending is unpredictable -- and that it isn't a bad thing. It makes a person interesting when you can't predict what choices they'll make and how things will end. 
After the conversation, I-330 pushes the narrator away and tells him that all Auditoriums will be closed after that night.