Ajñana

Ajñana was one of the nāstika or "heterodox" schools of ancient Indian philosophy, and the ancient school of Indian skepticism. It was a Śramaṇa movement and a major rival of early Buddhism and Jainism. They have been recorded in Buddhist and Jain texts. They held that it was impossible to obtain knowledge of metaphysical nature or ascertain the truth value of philosophical propositions; and even if knowledge was possible, it was useless and disadvantageous for final salvation. They were sophists who specialized in refutation without propagating any positive doctrine of their own.

All of our knowledge of the Ajñana come from the Buddhists and Jain sources. The Ajñana view points are recorded in the Buddhist Brahmajal Sutta and Samaññaphala Sutta and Jain Sutrakritanga. Along with these texts, the sayings and opinions of the Sceptics (ajñanikah, ajñaninah) has been preserved by Jain writer Silanka, from ninth century, commenting on the Sutrakritanga. Silanka considers sceptics as those who claim that scepticism is best or as those in whom no knowledge, i.e. scepticism, is evident. Apart from the specific technical meaning, Silanka also uses the word ajñanikah in a more general sense to mean anyone who is ignorant.

The traces of scepticism can be found in Vedic sources such as in the Nasadiya hymn and hymn to sraddha (faith) in Rigveda. In Brahmanas and Early Upanishads doubt regarding a person's existence after death is cast, while the Yajñavalkya argued for the impossibility of knowing the ultimate reality or the atman. However the flourishing of sceptical thoughts seems to have occurred in a period with diverse, conflicting, and irreconcilable theories, regarding morality, metaphysics, and religious beliefs. It is natural, in the absence of a commonly accepted criterion of truth, for some people to wonder if any theory could be true at all. The Sceptics specifically pointed to the conflicting theories of atman and the requirement of omniscience, and hence the criticism of omniscience, to obtain true knowledge. A proliferation of view points existed during the period immediately preceding the rise of Buddhism, as attested in the Buddhist and Jain texts. The Buddhist Brahmajal Sutta lists four types (or schools) of Sceptics along with fifty-eight other schools of thoughts, while the Jain Sutrakrtanga lists sixty-seven "schools" of Sceptics among three hundred and sixty-three different schools of thoughts. While the list is artificially constructed according to Jain categories, the four main schools of thought, Kriyavada, Akriyavada, Ajnanikavada, and Vainayikavada, and their subgroups must have existed. Thus, philosophical Scepticism is thought to have appeared around this historic time frame.

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