Liu Ren Shi Ke — often simply called Da Liu Ren (Great Liu Ren) — is one of the three supreme divination arts of classical China, collectively known as San Shi (Three Arts), alongside Qi Men Dun Jia and Tai Yi Shen Shu. Of the three, Liu Ren is considered the most accessible for individual consultation, making it the system most widely used by fortune tellers and diviners throughout Chinese history. The name "Liu Ren" refers to the six ren — the six instances of the heavenly stem ren (壬) within the sixty-cycle stem-branch system. The system uses a rotating arrangement of twelve "monthly generals" corresponding to the twelve earthly branches, plotted against a twelve-palace foundation structure, to create a chart called a shi ke (time pattern) for any given moment.

What makes Liu Ren Shi Ke remarkable is the depth of information it extracts from what might seem like a simple temporal coordinate. A full Liu Ren chart includes not just the surface energies of a moment but the relationships between four key divine entities: the Heaven General (Tianguan), the Ground Branch (Dizhi), the Year Stem (Niangan), and the Day Stem (Rigan). These four elements interact in specific patterns that indicate the quality of relationships, the likely outcome of actions, hidden obstacles, and favorable directions. Traditional texts contain hundreds of patterns with names like "Dragon Returning to the Ocean" or "Three Strange Meeting," each describing a specific configuration and its significance. Modern practitioners use Liu Ren for questions ranging from military strategy (its original application) to business timing, medical prognosis, and personal decisions. It requires years of study but rewards that study with an extraordinarily rich framework for understanding the interplay of time and circumstance.