Tolkien and the universal dream world

Sleep experience, especially dreaming, lies near the heart of JRR Tolkien's unfinished novel The Notion Club Papers (written 1945-6). One aspect of this is that there are multiple references to the idea that the dream world is a realm of experience which is universal - in other words, dreaming is a single, vast domain - with distinctive qualities, different from the waking state - that is potentially accessible by all people.
More at:
http://notionclubpapers.blogspot.co.uk/2017/05/the-universal-realm-of-dream-world-in.html