"really, it's just about the two opposing states of consciousness...
which don't really oppose at all.
See, in the waking world,
the neuro-system inhibits the activation of the vividness of memories.
This makes evolutionary sense.
It'd be maladapted for the perceptual image of a predator...
to be mistaken for the memory of one and vice-versa.
If the memory of a predator conjured up a perceptual image,
we'd be running off to the bathroom every time we had a scary thought.
So you have these serotonic neurons...
that inhibit hallucinations...
that they themselves are inhibited during REM sleep.
This allows dreams to appear real...
while preventing competition from other perceptual processes.
This is why dreams are mistaken for reality.
To the functional system of neural activity that creates our world,
there is no difference between dreaming a perception and an action and actually
the waking perception and action."

It's just as real as 'real life'.