The term Jain (in Sanskrit, Jaina) means someone who venerates the jinas. Jina (conqueror) in this context refers to one who, by conquering desires and aversions, achieves liberation from the bondage of worldly existence. Achieving such liberation is the object of Jain belief and practice.
Jains believe that the cosmos contains an infinite number of immaterial and indestructible souls (jivas). In common with other Indic traditions, the Jains also believe that each soul is reborn after death, and that the type of body it inhabits depends on the moral character of its deeds in past lives. According to Jainism, souls exist in every cranny of the cosmos: they inhabit the bodies of deities, humans, the inhabitants of hell, and plants and animals, and are also present in earth, water, fire, and air. Because the cosmos was never created, each soul has been wandering from one embodied state to another from beginningless time, and will continue to do so for infinite time to come unless it achieves liberation.
The cause of the soul's bondage is karma (action), which in other Indic religious traditions refers to the process by which one's good or bad acts give rise to consequences to be experienced in one's present or subsequent lives. The Jains, however, maintain that karma is an actual material substance (often likened to a kind of dust) that pervades the cosmos; it adheres to the soul, and the encumbrance of accumulated karmic matter is responsible for the soul's continuing rebirth. Karmic matter is drawn toward the soul by volitional actions, and its adhesion to the soul is a consequence of the emotional state of the actor. The passions, especially those of desire and aversion, create a moisture-like stickiness that causes karmic matter to build up on the soul.
To achieve liberation, therefore, one must avoid attracting more karmic matter and shed one's already existing accumulations. This is a complex and arduous process that begins with the awakening of faith in Jain teachings and ends with the removal of the last vestiges of the soul's burden of karmic matter. The liberated soul then rises to the abode of liberated souls at the top of the cosmos, where it will exist for all of endless time to come in a condition of omniscient bliss.
Avoiding violence is essential to one's progress toward liberation. Because violent actions are associated with the passions that contribute to the influx and adhesion of karmic matter, Jains are strongly committed to nonviolence (ahimsa). At a minimum, Jains should be vegetarian. Observant Jains avoid even vegetarian foods deemed to involve excessive violence in their acquisition or preparation. Root vegetables such as potatoes are proscribed because they are believed to contain multiple souls. Such restrictions are most onerous for monks and nuns who are debarred from activities that run the risk of harming even the humblest and most microscopic of living things. Lay Jains have been attracted to business precisely because buying, selling, and banking are activities that do not involve physical violence.
Ascetic practice is also essential to the attainment of liberation. Often likened to a fire that burns away karmic matter, ascetic practice subdues harmful passions that bring about the influx and adhesion of karmic matter and removes already existing karmic accumulations. Jain mendicants are renowned for the severity of their asceticism, and even lay Jains are expected to engage in periodic fasts and other ascetic practices.
The Jains maintain that the truth of their beliefs is guaranteed by the omniscience of their teachers. Known as tirthankaras ("ford-makers") or jinas, they are human beings who attained omniscience by their own efforts and without the guidance of other teachers, and who, before becoming fully liberated, imparted liberating knowledge to others. The Jains maintain that our section of the cosmos is subject to an eternally repeating cycle of world improvement and decline. Each ascent and descent is immensely long, and in each cycle exactly twenty-four tirthankaras successively appear. We are currently nearing the end of a descending era, and Mahavira was the twenty-fourth and hence the final tirthankara of our era and part of the cosmos. No new tirthankaras will appear until the next ascending period.
The concept of omniscience, seen as a natural quality of the soul when unoccluded by karmic matter, underlies Jainism's celebrated doctrine of epistemological relativity. Known as syadvad (the doctrine of "may be"), it holds that in contrast with omniscient knowledge, which incorporates all points of view simultaneously, ordinary knowledge discloses only partial glimpses of reality.