The world around you is not the real world. This is not merely a semantic distinction, but there is in reality a very great difference between the world we see and the physical world that we cannot see, and this difference is well known to science.
Mental Imagery, Hallucinations, and Dreams provide direct evidence that the mind is capable of constructing fully spatial representations that are analogous to the virtual world of the spatial robot discussed in the [robot analogy,] and that it uses these spatial representations in daily interaction with the world.
Evidence from neurophysiology and perceptual deficits caused by damage to specific brain areas provides further support for this notion.
Perhaps the most compelling evidence for a spatial integration stage in visual perception is the appearance of solid surfaces and in certain visual illusions.
There is a growing body of psychophysical evidence to indicate that the external world is perceived not as a symbolic abstraction, but rather as a solid spatial percept.