ABSTRACT
We all ask these kinds of questions to get where we want to go. Each landmark we use (the pub, the streetlight) is different, but the space we travel through seems much the same-just a void between destinations. We refer to space as “cluttered” when it becomes overly filled, and we look through space as if it is just air between one object and another. Yet space is also a thing, and regarding perception, it is a special kind of thing. Unlike outer space, perceptual space is not infinite. It has boundaries. When we look upward toward the sky, space has an end. It stops with the day’s blue sky or the night’s black background behind the moon and stars. Space is not a void in our mind’s eye. Its depth, volume, and boundaries are all part of the brain’s creations given to us in perceptual awareness. Just like objects, spaces have form and can be conceptually and physically different. The space inside a tennis ball is different from the space between the sun and the earth. The space between atoms is different from the space between houses. The spaces between a group of boundaries (Figure 1.1) have a form all their own, although we perceive them as a unified space behind foreground objects.
