________________ 102 Introduction from the akusala-malas. Only an arhat brings an end to these roots of all evil volitions. If the akusala-mulas are not annihilated till the attainment of arhatship and if they are incompatible with the kusala-mulas, how are we to explain the operation of kusala-malas or of kusala volitions in a mundane (laukika) existence ? Being incompatible they cannot operate simultaneously. Nor can they operate successively, for succession demands a certain element of homogeneity between the preceding and succeeding moments. If a kusala chitta were to follow an akusala chitta, then it will depend for its nature on a heterogeneous cause. It will amount to an admission of an unacceptable position that good springs out of evil or vice versa. The Theravadins avoid this dilemma by postulating a theory that the akusala and kusala chittas never follow each other without an intervening avyaklita (indeterminate, i.e. vipaka) chitta. An akusala chitta-vithi can be succeeded by a kusala chitta-vithi only after an interyention of a bhavanga-chitta, which is necessarily a vipaka-chitta. The Vaibhashikas seek to avoid this difficulty by postulating a chitta-viprayukta sanskara called prapti, a force which controls the collection of particular kinds of elements, and another samskara called aprapti which prevents such a collection. Thus, for instance, when an akusala chitta is followed by a kusala chitta the latter is brought into operation by prapti of the kusala dharmas which is at the same time assisted by the aprapti which prevents the rise of akusala dharmas. The Sautrantikas reject both these theories. They do not accept the theory of the Theravadins, presumably on the grounds that an avyaksita chitta is not more helpful than the akusala chitta, in as mush as both are equally inefficient to produce a kusala chitta. They reject the Vaibhashika dharmas called prapti and aprapti on the grounds that these in turn need to be produced by another prapti and aprapti, a position, which leads only to an infinite regress.
