What a thing is and what it means are not separate, the former being physical and the latter mental as we are accustomed to believe.
The meaning or value of a thing consists of what it affords.
The heart of the problem is not so much how we see objects in depth, as how we see the constant layout of the world around us. Space, as such, empty space, is not visible, but surfaces are.
Psychology is still trying to explain the perception of the position of an object in space, along with its shape, size, and so on, and to understand the sensations of color.
Hence it is that the shape of something is especially meaningful.
A mechanical encounter or other energy-exchange may cause tissue damage.
The abstract analysis of the world by mathematics and physics rests on the concepts of space and time.
