The dream holds true in half the total universe

In The Varieties of Religious Experience, William James observed that "The founders of every church owed their power originally to the fact of their direct personal communion with the divine."

   That “direct personal communion" has been conducted through dreams and visions and interior dialogue and observation of signs and marvels in the natural world, all facets of dreaming in the broader sense understood by our ancestors and by active dreamers in all cultures. James reminds us that religion without dreaming is divorced from its very origins.
   In a letter to Henry Rankin on June 16, 1901, he put it this way: "The mother sea and fountainhead of all religions lie in the mystical experiences of the individual, taking the word mystical in a very wide sense. All theologies and ecclesiasticisms are secondary growths superimposed."  Borrowing from his friend, the great British psychic researcher and scholar, Frederic Myers, James explained that "mystical consciousness" is related to the existence of an "extended subliminal self, with a thin partition through which messages make irruption."
   For most of us, it is through dreams that the subliminal self most frequently irrupts through that "thin partition" into everyday awareness.
   In Principles of Psychology, James offers these interesting reflections on the orders of reality we may enter in dreams, and why dreaming is our mode of experiencing half the "total universe":

The world of dreams is our real world whilst we are sleeping, because our attention then lapses from the sensible world. Conversely, when we wake the attention usually lapses from the dream-world and that becomes unreal. But if a dream haunts us and compels our attention during the day it is very apt to remain figuring in our consciousness as a sort of sub-universe alongside of the waking world. Most people have probably had dreams which it is hard to imagine not to have been glimpses into an actually existing region of being, perhaps a corner of the spiritual world.

And dreams have accordingly in all ages been regarded as revelations, and have played a large part in furnishing forth mythologies and creating themes for faith to lay hold upon. The 'larger universe,' here, which helps us to believe both in the dream and in the waking reality which is its immediate reductive, is the total universe, of Nature plus the Super-natural. The dream holds true, namely, in one half of that universe; the waking perceptions in the other half. 

Dwell with that last statement for a moment.  The dream "holds true" in half the "total" universe, and is our way to access and experience this reality. If James is correct, then if we have divorced ourselves from dreaming, we are only halflings, only half present in the universe.