Where do we draw the line?

A couple excerpts:

A line does not in reality exist to mark the boundaries of an object against its surroundings or against other objects. Tone, colour, three-dimensional vision and movement tell us where the edges of objects are in real life. The linear outline is a translation, an invented language, or rather the first phrases of a language with which we have learned to represent the visual world. - John Raynes

fig·u·ra·tive \'fi-g(y)ə-rə-tiv\ adj (14c) 1 a: representing by a figure or resemblance : EMBLEMATIC b : of or relating to representation of form in art <~ sculpture> 2 a: expressing one thing in terms usually denoting another with which it may be regarded as analogous : METAPHORICAL <~ language> b : characterized by figures of speech — fig·u·ra·tive·ly adv — fig·u·ra·tive·ness n - Merriam Webster's