Jainism schools like Nyaya Vaiseshika believe in reality of absolute time in contradistinction to Buddhists, followers of the Samkhya, and Vedantins who do not recognize the objective existence of real time. In tune with their religion-philosophy, Jains regard time as ajiva (non-conscious), eternal and without kaya (form or body).
Ajiva is one of the two principal categories of the knowable world, the other being jiva. The former comprises dharma, adharma, akasha, pudgala and kala. The present, past and future are considered as phenomenal time causing changes, and are thus relative time.
The followers of Nyaya Vaiseshika, on the other hand, hold the view that the notions of past and future are with reference only to the present and reckon time in terms of its actions also, thus distinguishing it from space which, according to hem, has no action. They believe that the present, past, and future are empirical divisions of time. The appearance of an effect, according to them, indicates the future; its persistence means the present; and its destruction means the past.
However, according to the Jain view, there is also niscaya kala (noumenal time) which is the basis or support for vyavahara kala (phenomenal time) and is the cause of changes in substances in diverse ways. Digambaras do not consider time as one and all pervasive and postulate that there are distinctive time-units corresponding to distinguishing human experiences. They regard these as ultimate time units or kalanus (atoms of time). The concept of indivisible and infinitesimal atoms of time is peculiar to Digambaras.