The history of making 2D art from a mostly 3D world goes back 12-40,000 years to cave paintings in France and Spain. As this marks some kind of beginning, one can put it together to realize it took modern humans about 160,000 years or so to develop an art form we can see today.
A hallmark of these original artistic efforts is the hand stencil: outlines of human hands carefully positioned in the composition. Such stencils also appear in cave art in Argentina, Africa, Borneo and Australia according to a National Geographic article from 2013 (http://news.nationalgeographic.com/news/2013/10/131008-women-handprints-oldest-neolithic-cave-art/). As a side note, apparently it is likely that most of the oldest hand stencils were made by women artists.
One can guess that these earliest images of hand prints and animals represent an effort to say “I was here, this is what I see.” Its language appears to be direct and sets the precedent for contemporary preschoolers outlining their hands in art class.
Later art can be seen as getting wordier, perhaps even to discuss a naval battle such as depicted by Pieter Bruegel the Elder in 1560 (The battle in the Gulf of Naples). See http://www.wga.hu/html_m/b/bruegel/pieter_e/12/01navalb.html for his story. Bruegel describes the weather, the number of ships, what kind they were, that some had caught fire, and manages to suggest a certain placid threat erupting from the ocean itself.
So in 40,000 or so years we’ve traveled from “I am here” to a battle narrative and yet more.
Figurative or representational art, that depicting reality as agreed upon—landscape, still life, people, social occasions, sports, food, everyday recognizable things—again translates a 3D world to a 2D surface. One manifestation of this is the painting genre of photorealism, now an honored contemporary practice. Oftentimes it serves to enhance the emotive quality that a photograph may lack while branding the artwork as the artist’s own by theme, palette, subject, etc. Art, by its inherent nature of discovery, continues to develop its language.
Ahh, but abstract art: What is it saying? Wiki gives a pretty good overview of its historical development: https://en.wikipedia.org/wiki/Abstract_art. Yet, keep in mind that art will typically continue to be defined, explored and written about by non-artists.
One idea holds that Abstract Expressionism is all about emotional or visceral states—those states typically impossible to describe in words. Color, form and line energy substitutes for any detailed psychological statement. For me, abstract art, free of worldly references, offers to define the non-verbal aspects of life and its countless dimensions.
And I also believe art will, by necessity, keep expanding its language. My work aims toward developing a visual inspiration that can be used by anyone to help fill in some existential blanks. For instance, repeat parallel lines may be suggesting time passes. To another those same lines may foremost represent a sense of security or order. Either or all is correct. Coupled with bright colors or dull, with simple or complex form arrangements, a viewer may receive endless illumination. It’s a matter of seeing with the heart, mind, eye, soul, and perhaps touch—a meditative state to extract personal significance from the nonverbal. I maintain faith that we are capable of such understanding and dimensional expansion.