Daniel Defoe’s “Robinson Crusoe” (post 3) 

“Like his author, Crusoe is saved by his ability to allow his inner voices to speak to each other. ‘Better than sociable’, he describes his time on the island. Voices allow externalisation of emotion; imaginary friends, they provide Crusoe with 'a great deal of comfort within’.” (1).

In contrast to Professor of English, Patricia Waugh, I see inner voices conversing, and imaginary friends in adults, as symptoms of multiple personality (the trait, not the disorder, since it does not cause him dysfunction or distress).

1. Patricia Waugh. “The novelist as voice hearer.” The Lancet, December 05, 2015. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)01118-6/fulltext#:~:text=One%20of%20the%20first%20fictional,his%20time%20on%20the%20island.