Ahimsa Paramo Dharma: non-violence is the highest religion. Violence and attachment attract karma, a sticky physical substance that clings to human souls, binding them to samsara. Jains can attain liberation by burning off these karmas through strict adherence to non-violence.
Ultimate Reality and Divine Beings
Jainism postulates no creator god. The unfortunate union of soul and matter propels the cycle of samsara. Tirthankaras are enlightened human teachers attributed with supernatural characteristics. The universe consists of three realms: hellish; earthly/heavenly; and that of siddhas (liberated souls).
Human Nature and the Purpose of Existence
Every sentient being has a soul mired in material karmic particles that block its spiritual path. Action, particularly action with attachment, attracts karma to the soul throughout successive reincarnations. Karma must be burned off in order to reach liberation.
Suffering and the Problem of Evil
All sentient beings do harm simply by existing. This harmful action and the karmas it generates are at the root of all suffering. The evil and violence inherent to this existence prove to Jains the absence of a creator god.
Afterlife and Salvation
Following liberation one's jiva ascends to the apex of the universe to join other siddhas. One can ascend to a heavenly realm due to good karmas accrued, but must return to a human incarnation in order to achieve final liberation.