The two schools directly based on the Vedic texts are:

• Mimamsa (or Purva-Mimamsa)
• Vedanta (or Uttara-Mimamsa)

Sad-darsana refers to the six orthodox (Astika) systems of Indian philosophy that recognize the authority of the Vedas. The names are:

1. Nyaya
2. Vaisesika
3. Samkhya
4. Yoga
5. Mimamsa
6. Vedanta

Meaning: 'Rta' refers to the cosmic, moral, and physical order that governs the universe.
Scripture: It is primarily found in the Rg Veda.

The Carvaka school believes material objects are composed of four elements:

• Ksit (Earth)
• Ap (Water)
• Tejas (Fire)
• Marut (Air)

Carvakas reject these entities because they cannot be perceived. Since perception is the only valid source of knowledge for them, anything that is not perceivable (like God or heaven) is considered non-existent.

The two primary sects of Jainism are:

• Digambara
• Svetambara

There are four Noble Truths (Catvari Arya Satyani). The Fourth Noble Truth (Dukkha-Nirodha-Gamini-Pratipada), which concerns the path to end suffering, is related to the Eight-fold Path.

Root Cause: Avidya (Ignorance) is the root cause of suffering.
Permanent Self: No, Buddha does not believe in a permanent self; he taught the doctrine of Anatta (No-Self).

The four schools are:

• Vaibhasika
• Sautrantika
• Yogacara (Vijnanavada)
• Madhyamika (Sunyavada)

Nyaya recognizes four sources of valid knowledge (Pramanas):

• Pratyaksa (Perception)
• Anumana (Inference)
• Upamana (Comparison)
• Sabda (Testimony)

The five members are:

1. Pratijna (Proposition)
2. Hetu (Reason)
3. Udaharana (Example)
4. Upanaya (Application)
5. Nigamana (Conclusion)

Samavaya is defined as an inseparable, eternal relation between two things where one exists residing in the other (e.g., the relation between a whole and its parts).

The two realities are:

• Purusa (Pure Consciousness)
• Prakrti (Primal Matter)

Advaita Vedanta recognizes six Pramanas:

• Pratyaksa, Anumana, Sabda, Upamana, Arthapatti (Postulation), and Anupalabdhi (Non-apprehension).

The two functions of Maya are:

• Avarana Sakti: The power to conceal the true nature of Brahman.
• Viksepa Sakti: The power to project the phenomenal world.

Indian philosophy, despite its diversity, shares several common characteristics:

• Spiritual Orientation: Aimed at Moksha or liberation from suffering.
• Law of Karma: Belief that every action has a consequence.
• Cycle of Rebirth (Samsara): Belief in the transmigration of the soul.
• Practical Necessity: Philosophy is seen as a way of life, not just an intellectual pursuit.
• Ignorance as the Root of Suffering: Avidya is identified as the cause of bondage.

The Carvaka metaphysics is strictly Materialistic:

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• Four Elements: Only Earth, Water, Fire, and Air are real because they are perceivable[span_60](end_span).
• Consciousness: It is a byproduct of matter, appearing when elements combine in a specific way, just as red color appears when betel leaf and lime are chewed together.
• Rejection of Soul: There is no soul independent of the body.
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• Rejection of God: Since God is unperceivable, the world is created by the spontaneous combination of elements (Svabhavavada)[span_64](end_span).

Pratityasamutpada is the central pillar of Buddhism. It means that everything arises in dependence on causes and conditions.

"That being, this arises; on the cessation of that, this ceases."

Visesa (Particularity):

• It is the category that accounts for the ultimate difference between eternal substances (like individual atoms of Earth).
• It is what makes one atom unique from another atom of the same type.
• Since this school emphasizes Visesa, it is named Vaisesika.

Concept of Brahman: Brahman is the ultimate, non-dual reality (Advaita). It is Nirguna (without attributes) and is described as Sat-Cit-Ananda (Existence-Consciousness-Bliss).