In geomantic omen, "Qi dissipates with the wind and stops when it meets water", "Dragon follows the water", "Shan Zhi, water treatment", "Look at the mountain first" and "No water, no feng shui" all prove the importance of water in geomantic omen. True water can give people vitality and prosperity, and it is an indispensable thing in people's lives. Virtual water does not have these functions, and some of them are evil, such as railways and highways, which cannot make Feng Shui "gather but not disperse".