Human eyes are highly developed organs evolved out of the brain's nervous tissue which migrated to the front of the face, nestled into protective bony sockets and grew transparent lenses, allowing a narrow spectrum of the electromagnetic vibrations of the cosmos (light) to fall directly into their exquisitly sensitive, velvety red retina (define). Almost all of the visual field is peripheral . At the very edges of the peripheral field the eye sees only movement.

DO THIS:(20 seconds)
Look straight ahead. Extend your arm directly out to your side from your body with your hand pointing forward. Dont move your eyes. SLOWLY move your arm forward around in front of you. Notice where you first see you fingers. Repeat this only this time wiggle your fingers as you slowly move your arm around. Notice that you see your wiggling fingers sooner.
Only a tiny (less than one percent), central area is capable of seeing with great acuity (define).

DO THIS:(2 minutes)
Mark two small black spots (the size of a period) a quarter inch (the width of a pencil) on a piece of white paper. Tape the paper on a well-lit wall. Stand a few feet away and notice that when you look at one dot, you cannot see the other as clearly as the one at which you are looking. Notice the feeling of your eyeballs moving as you look from one dot to the other, imagine a kind of "Click!" as you shift your eyes. Step back eight or ten feet and notice that you still have to look from one to the other to see each dot clearly. Continue moving away from the dotted paper until when you are looking at one dot, you see the other equally clear, and, although you may experience a shift of attention, your eyeballs are not moving. In you imagination, draw a circle through the two dots.

This circle represents the very tiny area of your field of vision that you use to see sharply. This sharp vision area (called the fovea) is also the only part of the retina that is capable of seeing hues. Unbelievable as it seems, the peripheral area is capable of seeing no hues. That we think we see hues there is a trick of memory. A simple brief scanning glance is enough for the brain to "map" them in!
Normally, when we look at something, we quickly scan it by jumping from interesting point to interesting point with our sharp vision area, relying on our peripheral vision to alert us to anything unusual. When we have done this to the extent that we feel we know what we are looking at well enough for our purposes, whatever they may be at the time, we feel we have looked at it. This manner of seeing the world is not learned: it's automatic. Except for reading, it is the way most people see all of the time.
Artists learn another way of seeing.