水流湿，火就燥

Explanation: Water flow to the wetlands at the fire to burn dry place. Referring to things of a similar temperament will phase induction. After metaphor for the inexorable law of development of things. 　　Source: "Easy to do": "water wet, dry the fire, the cloud from the dragon, tiger ...... wind from their kind too." Brief Account sparse:. "This two-phase flow in order to image a sense, the first on a wet place ; burnt their salary, first on dry place. "