An art thread, I love these.
Of course art is subjective, what may be art in my eyes, may not be in someone else's. There are many artist who choose to push this definition to the extreme. First one that comes to my mind is Marcel Duchamp, who took a urinal, signed it "R.Mutt", titled it "Fountain" and called it art. Second would be Mark Rothko, who likes to paint rectangles.
My four year old nephew could probably make it, is it art? The answer is entirely up to you.
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In my personal opinion, what I would classify as art needs to have some form of effort behind it, I dislike a piece if it looks like it took no time at all, that being said, I don't actually know if some of these artist spent a lot of effort on their work, maybe Rothko stared at a blank canvas for hours, got angry, ripped the painting up, started over half a million times trying to get these rectangles just right, Or maybe he just thought to himself "Hey I wanna paint rectangles and see how people react." The world may never know.