Most martial arts have an under lying philosophy. Martial Arts Schools in the United States stay away from anything that could be interpreted as religion. Some of the under lying philosophies and or religions of martial arts include Zen, Buddhism, Russian Orthodoxy to name a few. Some people believe that Tai Chi is a blending of Buddhism and Taoism. All of teachers I have trained under believe Daoism (Taoism) is the underlying philosophy of almost all styles of Tai Chi.
Lao Tzu is credited with the philosophy of Daosim
Little is truly known about the Chinese philosopher Lao Tzu (sometimes also known as Laozi or Lao Tze), who is a guiding figure in Daoism (also translated as Taoism), a still popular spiritual practice. He is said to have been a record keeper in the court of the central Chinese Zhou Dynasty in the 6th century B.C., and an older contemporary of Confucius. This could be true, but he may also have been entirely mythical—much like Homer in Western culture. It is certainly very unlikely that (as some legends say) he was conceived when his mother saw a falling star, or was born an old man with very long earlobes – or lived 990 years.
Lao Tzu is said to have tired of life in the Zhou court as it grew increasingly morally corrupt. So he left and rode on a water buffalo to the western border of the Chinese empire. Although he was dressed as a farmer, the border official recognised him and asked him to write down his wisdom. According to this legend, what Lao Tzu wrote became the sacred text called theTao Te Ching. After writing this, Lao Tzu is said to have crossed the border and disappeared from history, perhaps to become a hermit. In reality, the Tao Te Ching is likely to be the compilation of the works of many authors over time. But stories about Lao Tzu and the Tao Te Ching have passed down through different Chinese philosophical schools for over two thousand years and have become wondrously embellished in the process.