Taoist cosmology
Chinese concept of cosmology and celestial patterns have derived four emblems in the celestial heavens as the Green Dragon, the White Tiger, the Black Turtle and the Red Bird. These emblems are associated with the directions as follows:
Black Turtle- North , Green Dragon – East ,Red Bird – South and White Tiger- West. In Feng Shui it is important to ensure that the left , the Green Dragon is higher than the right, the White Tiger and that the back, the Black Turtle is higher than the front , the Red Bird.
The 12 stellar positions corresponded to the 12 symbolical animals in Chinese Horoscopes.
The orientation of the main door of a building is to be decided according to the date of completion of the building. The location and orientation of a building is made with reference to the Nine Stars. The site on which the building sits is subdivided into 24 parts.
For thousands of years the Chinese have been prejudiced against the northeast and south west as these directions are lacking in spirits of both heavenly and earthly essence.
Doing the right thing at the right time and at the right place is also an important consideration in Feng Shui because the cyclical movements and changes influence the harmonious disposition of things on earth and effect the entry of auspicious qi to the buildings.

