Visual scanning. We take visual inventory. We relate them to our experience in our past and push them into the present. The hierarchy of their value is weighed on that experience. About a month ago I was driving through a well to do neighborhood.  As I drove I watched people walking, tending yards and bringing in the paper. The experience of my past steered the order of hierarchy without a second thought. This image was one of the first to be put on paper. 

Graphite and charcoal stick on paper  

Graphite and charcoal stick on paper