I believe that there are two kinds of art, good and bad. What makes a work of art good or bad is not a matter of personal opinion, but is universal, constant. What makes a work good, successful, beautiful does not change with time, geography, social structure, prevailing tastes or one’s individual preferences. After having tested his aesthetic concepts in literally thousands of works of different periods, in different styles, in different media, I say that Eli Siegel’s Theory of Opposites is the key to what is good or beautiful in art. I have seen that the greater the work of art, the richer, more surprising and subtle the play and fusion of the opposing qualities in it. In a bad work of art, the opposites are present, but either they fight too much, or they are limply there.
When Eli Siegel showed that what makes a work of art beautiful—the oneness of opposites—is the same as what every individual wants, it was one of the mightiest and kindest achievements of man’s mind.
from Aesthetic Realism: We Have Been There—
and The Art of the Print