Broadly speaking, the theme “action” is recurrent in Indian philosophy in at least three context: 1. Action as an evidence for the existence of a Self, 2. Action in the context of language use, 3. Moral Action (I will not distinguish between moral and ethics).
1. Action as an evidence for the existence of a Self
Indian darśanas share commonly agreed notions and terms. One of those is the idea of categories as actually existing classes into which the reality can be organized. The most ancient ones are probably substance, quality (guṇa) and movement (karman). The latter is of direct relevance for the present study. The Vaiśeṣika system, which fixed as such at an early stage (so Frauwallner), does not sharply distinguish between movements and intentional actions. Both are described as movements of atoms (which are conceived as the minutest particles of matter, unchangeable and eternal). Their difference lies only in the fact that the first ones are produced by material causes, the latter by effort (prayatna). Their development, though, follows the same causal scheme. Prayatna is again determined by volition and that by desire or aversion. A similar causal scheme is adopted by Nyāya and later Vaiśeṣika as well. As remote causes of desire and aversion either non-knowledge (erroneous knowledge, leading to an erroneous attachment to worldly things) or dharma and adharma (merit and demerit) are mentioned. Nyāya authors make the string longer by adding before the remote cause a “connection with a recollection” (smṛtyanubandha) as a determinant for the arousal of volition and then of efforts.