I believe, and this is just me speculating, that the reason they didn’t do with TS4 what they did with TS3 writers is because if sims lived an incredibly long time and wrote a lot of books, it REALLY bogged down the game. When little things like that accumulate it becomes very difficult to load a household. Like the simmer said above, you can create copies of books your author writes by placing the original on the lot somewhere and making copies (for a fee), and then taking them to the local library if you so choose. I haven’t actually tested that last part yet, but I get what you’re going for. I wish they had included this feature as well.