The fundamental reality in the Daoist understanding is divided in “nothing” and “everything.” The existence of one gives life to the opposite. The existence of everything gives purpose to nothing. One cannot exist without the other, and so the coexistence can be called the way of nature.
The principles of Yin and Yang can be applied to internal practice. (Tai Chi, Kung Fu, Qi Gong, Nei Gong and so on)
The interaction of soft and hard gives relevance to the understanding of harmony which is the purpose of Tai Chi Quan.
To be in harmony between Yin and Yang means to practice internal balance on all levels and can also be called the way of nature.
To excel in speed, one must be slow.
To be powerful, one must be relaxed.
To stand on one leg, one must be rooted to the earth.
This paradox is only an example how Daoist masters find the actual meaning of one power. The understanding of this principles can significantly enhance your actions.