The connection of action and result

No matter how one conceives it, the action is the chief element of a theory of causality. An action is the cause of an effect (be it internal or external). However, the link between action and result is not always fix: the same action of seeding, watering, etc. may lead to abundant rice plants or not. In this case, one might object that the other causes, such as the soil, differ. But what about the action of studying in the case of young children? It may lead to different results or even to no result at all. Indian thinkers had before them an even more striking example, the ritual action. Sacrifices are taught in the Veda to lead to a certain result (e.g., cattle, happiness, a son, the conquest of a village, …). However, by the end of the sacrifice, (usually) no result arises. And at the time the result (allegedly) arises, the action is long extinguished.

In order to explain such incongruities, one has to postulate something extra bridging the gap between action and result,

This can be an apūrva potency, that is, an unseen potency, "which did not exist before" the action. The apūrva is brought about by the action and eventually leads to the result. Through this intermediation, the action can still be said to be the cause of the result.

Else, one can try to detect additional factors, such as the soil in the case of rice plants. The apūrva is an external factor, but there are also factors residing in the agent, such as the saṃskāras. These are traces left by the action and deemed to ripe at a successive time. A Vaiśeṣika text (PDhS 8.21) describes them as "quality of the self (ātman)". However, post Vasubandhu Buddhists (especially Yogācāra ones) will theorise the existence of saṃskāras independent of a subject.

Last, one can amplificate the sphere of application of karman and postulate that an action initiates a chain of causes and effects which will. eventually lead to a result. This may happen even in a remote time, because the link cause-effect is not interrupted by the end of the physical body. Through this theory, "karman" will eventually be used (most of all in the West) as the theory representing one's destiny as causally determined by one's previous actions.

The apūrva-solution might have been the most ancient one, but it remained current in Mīmāṃsā and (as "adṛṣṭa") in Vaiśeṣika.

Theories about saṃskāras are already available in pre-Vasubandhu Buddhism and they are extremely influential in different theories of causation, each of them stressing their inhering in the subject (Hindū schools) or their independent existence, possibly within a stream of consciousness (Yogācāra Buddhism, 4th c. onwards). As in the previous section, hence, Buddhism emphasised the role of a subject-independent action and bearer of the action, against non-Buddhist schools, which by and large moved from direct realism to a subject-based one.