|Entrance to the 19th Century American Art, Sculpture Gallery at the Art Institute of Chicago|
Before Picasso, Pollack, Klee and other artists of the Modern/Abstract Art era, artist dealt with abstract concepts by using the human figure. An example is the sculpture "Truth" by Daniel Chester French, the phenomenal 19th Century sculptor who also created the famous seated portrait of Lincoln for the Lincoln Memorial in Washington D.C.
|Truth, Plaster, 1900|
The following text is from the info plaque next to a plaster working model of the statue at the Art Institute of Chicago:
Daniel Chester French, American, 1850-1931 was commissioned to create six allegorical figures, representing Bounty, Courage, Integrity, Prudence, Truth, and Wisdom, for the facade of the Minnesota State Capitol, in Saint Paul. This plaster statue is a working model and is half the size of the marble figure that appears, paired with Integrity, on the building. In this portrayal of Truth, French used symbols drawn from Classical and Renaissance sources. The mirror she holds reflects life without illusions; her partial nudity alludes to the nature of truth.
If the term "abstract" is taken to refer to such intangible concepts as "Truth", "Beauty", "Wisdom", etc., then I think artists have been making "Abstract Art" long before modern times.