Our brains react to visual stimulus, constantly judging whether they like a certain painting or not. One might get attracted to a work of art while the same thing doesn't do anything to others. There is no standard criteria for beauty. Beauty is in the eyes of the beholder.
I think beauty comes from highly ordered thing, in which there is a definite patterns. Beauty means planned design.
I designed this to maximize the unexpectedness of turns in every lines. It is this aspect that gives this work exceptional beauty.
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