Indian Philosophy: Schools and Their Core Ideas

Introduction

Indian philosophy (Bhāratīya Darśana — 'ways of seeing') comprises a diverse body of intellectual traditions dating back to the Vedic period (c. 1500 BCE). These schools systematically examine epistemology (what is knowledge), metaphysics (what is reality), ethics (how to live), and soteriology (how to attain liberation). The classical framework classifies schools into Āstika (orthodox, accepting Vedic authority) and Nāstika (heterodox, rejecting Vedic authority).

The Āstika (Orthodox) Schools — Ṣaḍ-Darśana (Six Schools)

These six schools accept the Vedas as authoritative but hold divergent philosophical positions.

1. Sāṃkhya

• Founder: Sage Kapila (Sāṃkhya Kārikā by Īśvarakṛṣṇa is the earliest complete text)
• Core Idea: Radical dualism of Puruṣa (consciousness/pure awareness) and Prakṛti (primordial matter/nature). The material world evolves from Prakṛti through a process of 23 tattvas (principles). Liberation (kaivalya) is achieved by discriminating between Puruṣa and Prakṛti.
• Epistemology: Accepts three pramāṇas (valid means of knowledge) — pratyakṣa (perception), anumāna (inference), śabda (testimony).
• Influence: Foundation for Yoga philosophy and Vedantic discourse.

2. Yoga

• Founder: Patañjali (Yoga Sūtras, c. 2nd century BCE)
• Core Idea: Practical application of Sāṃkhya metaphysics. Liberation achieved through Aṣṭāṅga Yoga (eight limbs): Yama (restraints), Niyama (observances), Āsana (postures), Prāṇāyāma (breath control), Pratyāhāra (sense withdrawal), Dhāraṇā (concentration), Dhyāna (meditation), Samādhi (absorption).
• Key Concept: Chitta Vṛtti Nirodha — cessation of mental fluctuations.
• Distinction from Sāṃkhya: Introduces Īśvara (a special Puruṣa, not a creator god but a transcendental model).
• Kriyā Yoga: Tapas (austerity), Svādhyāya (self-study), Īśvara Praṇidhāna (surrender to God).

3. Nyāya

• Founder: Sage Gautama (Nyāya Sūtras)
• Core Idea: Logical realism. Focus on correct reasoning and valid knowledge as the path to liberation.
• Epistemology: Sixteen categories (padārthas) of which four pramāṇas are central — perception, inference, comparison (upamāna), and testimony.
• Inference (Anumāna): Developed a rigorous five-step syllogism (pañcāvayava) — proposition, reason, example, application, conclusion.
• Significance: Foundational to Indian logical and analytical traditions.