The Fine Line Between Reality and Imaginary
nautil.us
nautil.us
(I never want to see that video of the bear and the basketballs ever again.)
All perception is imagination. We can only perceive what we imagine to perceive. I can't 'see a ball' if I don't know what a ball is. Our vision system in particular only samples a small fraction of the visual field and fills in the rest with guesses that fit our past and recent experiences.
This is less about imagination seeming real than it is about perception of real things under normal conditions being powered by imagination.