The nāstika schools

The nāstika schools are (in chronological order):

• Cārvāka, a materialism school that accepted free will exists
• Ājīvika, a materialism school that denied free will exists
• Buddhism, based on the teachings and enlightenment of Siddhartha Gautama
• Jainism, based on the belief in ahimsa or non-violence towards all living beings

Each school of Hindu philosophy has extensive epistemological literature called Pramana-sastras.

In Hindu history, the distinction of the six orthodox schools was current in the Gupta period "golden age" of Hinduism. With the disappearance of Vaisheshika and Mīmāṃsā, it became obsolete by the later Middle Ages, when the various sub-schools of Vedanta (Dvaita "dualism", Advaita Vedanta "non-dualism" and others) began to rise to prominence as the main divisions of religious philosophy. Nyaya survived into the 17th century as Navya Nyaya "Neo-Nyaya", while Samkhya gradually lost its status as an independent school, its tenets absorbed into Yoga and Vedanta.