the bounding line as primary human language

Surviving human artifacts tell us something about the way that we seem to be wired. Some of the earliest examples of visual expression are created by the use of elegant contour line drawing:

Lascaux, France

This is interesting to me, because the bounding line is entirely a human abstraction, and has persisted throughout history:

Leonardo Da Vinci

In different time periods:

Medieval Westminster, U.K.

In all parts of the globe:

Japanese Ukiyo-e Block Print

Draw your attention (pun only half-intended) to the fact that black lines do not actually hold in the world around you. Line work is, instead, a human language short-hand to show where one object ends and another begins. It's all about the perception of edges. So what parts of an object are most important for determining a contour? What can be left out?

David Hockney

Egon Schiele

Ingres

Student drawing