Novelists keep journals and have “waking-dreams” so that alternate personalities, who are usually not co-conscious, can communicate

In multiple personality, many alternate personalities are not co-conscious (they are not aware of each other). Or, they may have one-way awareness: “B” is aware of “A,” but “A” is not aware of “B.” Or, they may have indirect knowledge: “C” has seen books bearing “A’s” name. Or, personalities may just want to express themselves.

There are several ways for an alternate personality to send a message. If “B” hates “A’s” necktie, “B” can throw it out, but that is dysfunctional. A better way is for “B” to verbalize his complaint, which “A” will experience as a voice in his head or a loud thought.

Since novelists may be keeping a journal anyway—to collect and work on things of potential use in their writing—“B” can make an entry in the journal for “A” to see. Seeing the entry, “A” might realize that he has an alternate personality, but most novelists probably think of it as a message from their “unconscious” or “shadow,” a new character, or their literary muse.

When voices and journal-entries do not suffice, the novelist may have a “waking-dream,” in which they meet the alternate personality and see what the alternate personality wants them to see. The novelist calls this a “waking-dream” rather than a hallucination, since sane people have dreams and crazy people have hallucinations, and they are clearly sane, just creative.

Henry James called it “the madness of art.”