Readymades:

Marcel Duchamp,

“In Advance of the Broken Arm,” (1915)

(right top)

Marcel Duchamp: (1887-1968) French artist, Dada, Surrealism; provoked the public and art world to (re)consider what is art.  Developed out of symbolism (Odilion Redon), cubism and fauvism (color over representation, i.e., Matisse, Derain, Braque); Dada inspired his “readymades,” (though, note that in this, he follows an American vein of dada (re: journal The Blind Man) more than its European counterpart, the latter was more morbid and political, the former more pop).  Readymades (ca. 1915) were found art in its most basic sense (the urinal, the coat peg, the shovel); more developed notions used found objects to them make art (bicycle wheel on stool, his first piece).

Cf.: http://www.understandingduchamp.com/

Also: Thierry de Duve, Kant After Duchamp (MIT/October Books, 1998)

Duchamp’s “Fountain” (1917, 2nd right), “Hat Rack” (3rd right), “Bottle Rack” (1914, 4th right)

Jasper Johns “Flag” (1954-55, bottom right)

Jasper Johns: (b. 1930) American painter and printmaker (GA, SC, NYC, CN); not in Dada readymade vein like Duchamp, et al, [but, he is (oddly) described as a Neo-Dadaist] but, his flag paintings do share this same spirit of making a non-art-object into art.  His “Flag” (1954-55) was done with encaustic, oil, and collage on fabric then mounted on plywood; he did many variations of the flag. 

(all art is copyrighted by owning artist

or estate, all other photographs are my own,

all sources cited when known)