  The double function of this cognitive awareness as a conditioned and  conditioning factor within the overall dynamics of the five  aggregates is explained in causal terms by means of an analysis of  the underlying factors that play a role in the arising of each  cognitive event. The lists of the types of causes, conditions, and  results in the Abhidharma discourse of causality vary only slightly  from school to school. The classical Sarvāstivāda theory of causality, for instance, explains the patterns of conditioning  through the intermediary of six causes (hetu) and four types of conditions (pratyaya), as follows (see AKBh ad  II 49–73):