'cause', condition, reason; (Abhidhamma) root-condition. In sutta usage it is almost synonymous with paccaya, 'condition', and often occurs together with it ('What is the cause, what is the condition', ko hetu ko paccayo).

In Abhidhamma, it denotes the wholesome and unwholesome roots (mūla, q.v.). In that sense, as 'root-condition' (hetu-paccaya; s. paccaya), it is the first of the 24 conditions given in the introduction to the Patthāna (s. Guide, p. 117). The Dhs (1052-1082) and Patthāna (Duka-patth; Guide, p. 144) have sections on roots (hetu). - The term is also used (a) for the classification of consciousness, as sa-hetuka and a-hetuka, with and without concomitant root-conditions; (b) for a division of rebirth consciousness into ahetuka, dvihetuka and tihetuka, without, with 2, or with 3 root-conditions (s. patisandhi).

Ahetuka-ditthi, the false view of the uncausedness of existence; s. ditthi.