According to the passage, what did nature represent to Isadora Duncan?

Many artists late in the last century were in search of a means to express their individuality. Modern dance was one of the ways some of these people sought to free their creative spirit. At the beginning there was no exacting technique, no foundation from which to build. In later years, trial, error, and genius founded the techniques and the principles of the movement. Eventually, innovators even drew from what they considered the dread ballet, but first they had to discard all that was academic so that the new could be discovered. The beginnings of modern dance were happening before Isadora Duncan, but she was the first person to bring the new dance to general audiences and see it accepted and acclaimed.
     Her search for natural movement form sent her to nature. She believed movement should be as natural as the swaying of the trees and the rolling waves of the sea, and should be in harmony with the movements of the Earth. Her great contributions are in three areas.
     First, she began the expansion of the kinds of movements that could be used in dance. Before Duncan danced, ballet was the only type of dance performed in concert. In the ballet the feet and legs were emphasized, with virtuosity shown by complicated movements. Duncan performed dance by using all her body in the freest possible way. Her dance stemmed from her soul and spirit. She was one of the pioneers who broke tradition so others might be able to develop the art.
     Her second contribution lies in dance costume. She discarded ballet shoes and stiff costumes. These were replaced with bare feet, and unbound hair. She believed in the natural body being allowed to move freely, and her dress displayed this ideal.
     Her third contribution was in the use of music. In her performances she used the symphonies of great masters, including Beethoven and Wagner, which was not the usual custom.
     She was as exciting and eccentric in her personal life as in her dance.