Six Schools, Six Ways of Seeing the World

Indian philosophy is often presented as one voice. In fact it was a long, lively argument. Schools wrote short, dense root texts called sūtras, and then commentators spent centuries explaining, defending and attacking them.

Six schools came to be grouped together as the classical "orthodox" systems. Each one has a big question it cares about most, a key text, and a central idea. The table below lines them up on the same three rows so you can compare them at a glance.

The six are traditionally grouped into three pairs that share a lot of ground: Nyāya with Vaiśeṣika, Sāṃkhya with Yoga, and Mīmāṃsā with Vedānta.¹ Within each pair, one school tends to supply the theory and the other the method, or one focuses on knowledge and the other on the world.

The pairing is a teaching convenience, not a family tree. Schools borrowed from and argued with each other, and with Buddhist and Jain thinkers, across every pair.

These six are called āstika because they accept the authority of the Vedas. Buddhist, Jain and Cārvāka (materialist) schools are called nāstika because they do not.¹

The labels describe a position on Vedic authority, not a ranking. The nāstika schools are just as much part of India's philosophical conversation, and many of the sharpest arguments in the classical texts are between the two sides.

Vedānta itself split into several sub-schools that disagree on the most basic question of all: how the self relates to ultimate reality. Advaita says the self and Brahman are not two. Viśiṣṭādvaita says the self is real and distinct, yet inseparable from Brahman. Dvaita says they are eternally distinct.²

The argument was never settled, and that's the point. These schools model a way of disagreeing carefully, with rules of evidence and respect for the strongest version of the other side.