An encyclopedia stands for the whole of what can be known, set out in order. Dream books read it as curiosity, or as pressure to have every answer ready.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.