The cause and condition express all kinds of relationship between the cause and effect, and interdependent reliance between all things. All sects of Indian and Chinese Buddhism see the concept of the cause and condition as important. Sarva^stiva^din of Abhidharma Buddhism would like to explain the cause and effect relationship among all things, and created “Six-cause Sayings”. Sarva^stiva^din divided “causes” into six categories, “conditions” into four kinds, and “effects” into five categories. It also explained and exerted these concepts, and built a complete structure of causes, conditions, and effects. It is the famous theoretic system of six causes, four conditions, and five effects. The author tries to analyze the established background of the theory of six causes and four conditions, for understanding that the creation of the theory is for against the popular no-cause theory and uneven-cause theory, to reveal the creation of all things, and to decide that every thing has a cause. She also would like to interpret the concepts of “the real existence of three states” and “real existence of causes and conditions” though “Six-cause saying”, and to refute the heresy of “causes and conditions are unreal”. Besides, from the ten conditions of Sāriputrābhidharma-āstra of the early Theravada, she wants to discuss the six causes and four conditions of Sarva^stiva^din and organize the development of the saying of the cause and condition of Abhidhammatthasangaha. Then through the analysis of six causes, four conditions, and five effects, she finds out the relationships among the three states of the cause, condition, and effect. The analysis of “The Theory of the Six Causes and Four Conditions” of Sarva^stiva^din is not merely a linger cause and effect relationship, but an expression of complex relationship. Also, from the interpretation of the six causes and four conditions, which shows the core of analysis is interior psychological movement. On the one hand, Sarva^stiva^din mentions four conditions; on the other hand, it also cares about the analysis of causes. Therefore, the theory of causes and conditions become more completed, and people call it “The Sect of Cause Expressing”. However, it still had some imperfect parts, so at that time, there were still interior or exterior opposing voices.
