James J. Gibson

There has been a great gulf in psychological thought between the perception of space and objects on one hand and the perception of meaning on the other.

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.

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.

The meaning or value of a thing consists of what it affords.

I also assume that they are not simply the physical properties of things as now conceived by physical science. Instead, they are ecological, in the sense that they are properties of the environment relative to an animal.

The abstract analysis of the world by mathematics and physics rests on the concepts of space and time.

The human young must learn to perceive these affordances, in some degree at least, but the young of some animals do not have time to learn the ones that are crucial for survival.