Ajivika (Sanskrit; IAST: ) is one of the nāstika or "heterodox" schools of Indian philosophy. Believed to be founded in the 5th century BCE by Makkhali Gosāla, it was a Śramaṇa movement and a major rival of Vedic religion, early Buddhism, and Jainism. Ājīvikas were organized renunciates who formed discrete communities. The precise identity of the Ājīvikas is not well known, and it is even unclear if they were a divergent sect of the Buddhists or the Jains. Original scriptures of the Ājīvika school of philosophy may once have existed, but these are currently unavailable and probably lost. Their theories are extracted from mentions of Ājīvikas in the secondary sources of ancient Indian literature. The oldest descriptions of the Ājīvika fatalists and their founder Gosāla can be found both in the Buddhist and Jaina scriptures of ancient India. Scholars question whether Ājīvika philosophy has been fairly and completely summarized in these secondary sources, as they were written by groups (such as the Buddhists and Jains) competing with and adversarial to the philosophy and religious practices of the Ājīvikas. It is therefore likely that much of the information available about the Ājīvikas is inaccurate to some degree, and characterizations of them should be regarded carefully and critically. The Ājīvika school is known for its Niyati ("Fate") doctrine of absolute fatalism or determinism, the premise that there is no free will, that everything that has happened, is happening and will happen is entirely preordained and a function of cosmic principles. The predetermined fate of living beings and the impossibility to achieve liberation (moksha) from the eternal cycle of birth, death, and rebirth was the major distinctive philosophical and metaphysical doctrine of their school of Indian philosophy. Ājīvikas further considered the karma doctrine as a fallacy. Ājīvika metaphysics included a theory of atoms which was later adapted in the Vaiśeṣika school, where everything was composed of atoms, qualities emerged from aggregates of atoms, but the aggregation and nature of these atoms was predetermined by cosmic laws and forces. Ājīvikas were mostly considered as atheists. They believed that in every living being is an ātman—a central premise of Vedic and Jainism. Ājīvika philosophy, otherwise referred to as Ājīvikism in Western scholarship, reached the height of its popularity during the rule of the Mauryan emperor Bindusara, around the 4th century BCE. This school of thought thereafter declined, but survived for nearly 2,000 years through the