Why this matters now
The six orthodox schools and the heterodox systems are a prelims staple — pairing each school with its core idea/founder is commonly asked.
The six orthodox (astika) schools
The six astika schools accept the authority of the Vedas: Samkhya (dualism — Purusha & Prakriti, Kapila), Yoga (Patanjali, the eightfold path), Nyaya (logic, Gautama), Vaisheshika (atomism, Kanada), Mimamsa (ritual/Vedic interpretation, Jaimini), and Vedanta (Upanishadic philosophy — Advaita of Shankara, etc.).
The heterodox (nastika) schools
The nastika schools reject Vedic authority: Charvaka/Lokayata (materialism, by Brihaspati), Buddhism and Jainism. These offered alternative paths to liberation and ethics, challenging ritualism and caste.
Significance
Indian philosophy explored metaphysics, epistemology, logic, ethics and liberation (moksha), and shaped Indian religion, science and culture. Concepts like karma, dharma, yoga and non-dualism (Advaita) have had enduring global influence.
UPSC angle
Know the 6 astika schools and founders (Samkhya-Kapila, Yoga-Patanjali, Nyaya-Gautama, Vaisheshika-Kanada, Mimamsa-Jaimini, Vedanta), and the nastika trio (Charvaka, Buddhism, Jainism).
Frequently asked questions
What are the six orthodox schools of Indian philosophy?
Samkhya, Yoga, Nyaya, Vaisheshika, Mimamsa and Vedanta.
What distinguishes astika from nastika schools?
Astika schools accept the authority of the Vedas; nastika schools (Charvaka, Buddhism, Jainism) reject it.
What is Advaita Vedanta?
The non-dualistic school of Vedanta, most associated with Adi Shankaracharya.
What is the Charvaka school?
The materialist (Lokayata) school that rejected the Vedas, the soul and life after death.