The present paper investigates the interpretation of the “Three Time Periods” doctrine of the Vaibhasika and the Sautrantika Following Scriputre in the Abhidharmakosa-bhasya, according to the perspective of the mshims mdzod, the major Tibetan commentary on the Abhidharmakosa. This paper consists of two main parts, the interpretation of Dharmatrata and Vasumitra's assertions, and the description of the Sautrantika Following Scripture's view about past and future periods in the two truths theory. It is pointed out that Dharmatrata's position is from the viewpoint of two truths, and Vasumitra's is from the relation between the entity of existence and its function, while the Sautrantika Follsowing Scripture's negation of substantial entity of past and future is prescribable as mere stipulation, namely conventional truth in the classification of phenomena.
