Is there an Orthodox Hinduism?
Today all most all of Hinduism is Orthodox. Due to the classification of Buddhism and Jainism as separate religion they are no longer treated as part of Hinduism. Hence, as what is left in Hinduism is being primarily based on the Vedas (the revealed scriptures) all of Hinduism is orthodox.
The definition of unorthodox in Hinduism is Veda neendako nâstikaha. That is, the school of thought that doesn't accept authority of the Vedas is unorthodox. Previously Buddhism, Jainism and Ajivika school of thought came into formation in India by rejecting the Vedas, hence they were considered unorthodox. But after their classification as separate religion, most of Hinduism is Orthodox except certain sects that follow scriptures that are not based on the Vedas.
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