From the area of colors, black and white is a classic pattern. The white paper seems whiter when it is with a black dot, and black sky felt blacker when a star is shinning. Most of the designers like to choose black and white in the field of costumes or furniture, and most of business suit are black coat with white shirt.
In the kingdom of literature, black can be seen as bad people, evil behavior, so Chinese Peking opera chose black mask for the bad role, and evils are usually in black cloak. White means pure and not be polluted yet, innocent girls are often described to wear white dress like the white lily.
Black and white is contrary, and each makes the other excellent.
Same situation exists on the black swan and the white swan.
Most swans are white first, and they turn black at the end. Few black swans change to be white. The changing need a long time in daily life, the time is so long that you can not even realize it.
Art is originated from and different from life. Some kind of arts is amazing at their fast speed; some kind of art is amazing exquisite, and some is amazing at its fabulous looks.
The movie Black Swan tells about the art of ballet.
As a ballet dancer, act as the white swan only need the character of innocent, acting the black swan needs great energy. It is hard to be both. At the beginning of the performance you are clean as the white snow, but several minutes later you are evil and seduce the prince.
If you want to play a black role, you have to pretend yourself being too white, sometimes the liabilities of being white is strong and need great efforts.
In order to play both roles well, you have to dig the potential deeply to seek your own possibilities. And you have to get over big difficulties.
At the end of the movie, the dancer was successfully act two roles and found her was hurt on her bell by herself.