China - Taoism
Tao is the essence or substance of the Universe. The Tao is the flow of the Yin and the Yang in the Universe, the two types of “Qi.” Yin and Yang are opposite forces, that when balanced, work together. To be in accord with the Tao is to be in accord with the flow of the Universe. Enlightenment is developing one’s intuition and becoming directly aware of the Tao, the dance of life. In such circumstances, the enlightened person's every action would be correct and timely and would always lead to the most favorable outcome.
Qi, the Yin and Yang essence of the Universe runs throughout our human bodies and throughout nature as well. Acupuncture was developed to correct imbalances in the energy or Qi flows in the human body. The first record of Acupuncture is found in the 4,700 year old Huang Di Nei Jing (Yellow Emperor's Classic of Internal Medicine). This is said to be the oldest medical textbook in the world. Yin is signified by female attributes, passive, dark, cold, moist, that which moves medially, and deficient of Yang. Yang is signified by male attributes, light, active, warm, dry, that which moves laterally, and deficient of Yin. Nothing is completely Yin or Yang. The Tao is the universal symbol describing the constant flow of Yin and Yang forces. One will notice that within Yin, there is Yang, and within Yang, there is the genesis of Yin.