Purusha in the context of "Anattā"

Āstika (Sanskrit: आस्तिक, IAST: āstika) and nāstika (Sanskrit: नास्तिक, IAST: nāstika) are mutually exclusive terms that modern scholars use to classify the schools of Indian philosophy as well as some Hindu, Buddhist and Jain texts. The various definitions for āstika and nāstika philosophies have been disputed since ancient times, and there is no consensus. One standard distinction, as within ancient- and medieval-era Sanskrit philosophical literature, is that āstika schools accept the Vedas, the ancient texts of India, as fundamentally authoritative, while the nāstika schools do not. However, a separate way of distinguishing the two terms has evolved in current Indian languages like Telugu, Hindi and Bengali, wherein āstika and its derivatives usually mean 'theist', and nāstika and its derivatives denote 'atheism'.

Still, philosophical tradition maintains the earlier distinction, for example, in identifying the school of Sāṃkhya, which is non-theistic (as it does not explicitly affirm the existence of God in its classical formulation), as āstika (Veda-affirming) philosophy, though "God" is often used as an epithet for consciousness (purusha) within its doctrine. Similarly, though Buddhism is considered to be nāstika, Gautama Buddha is considered an avatar of the god Vishnu in some Hindu denominations. Due to its acceptance of the Vedas, āstika philosophy, in the original sense, is often equivalent to Hindu philosophy: philosophy that developed alongside the Hindu religion.

Samkhya or Sankhya (/ˈsɑːŋkjə/; Sanskrit: सांख्य, romanized: Sāṅkhya) is a dualistic orthodox school of Hindu philosophy. It views reality as composed of two independent principles, Puruṣa ('consciousness' or spirit) and Prakṛti (nature or matter, including the human mind and emotions).

Puruṣa is the witness-consciousness. It is absolute, independent, free, beyond perception, above any experience by mind or senses, and impossible to describe in words.

Yoga philosophy is one of the six major important schools of Hindu philosophy, though it is only at the end of the first millennium CE that Yoga is mentioned as a separate school of thought in Indian texts, distinct from Samkhya. Ancient, medieval and modern literature often simply call Yoga philosophy Yoga. A systematic collection of ideas of Yoga is found in the Yoga Sutras of Patanjali, a key text of Yoga which has influenced all other schools of Indian philosophy.

The metaphysics of Yoga is Samkhya's dualism, in which the universe is conceptualized as composed of two realities: Puruṣa (witness-consciousness) and Prakṛti (nature). Jiva (a living being) is considered as a state in which puruṣa is bonded to Prakṛti in some form, in various permutations and combinations of various elements, senses, feelings, activity and mind. During the state of imbalance or ignorance, one or more constituents overwhelm the others, creating a form of bondage. The end of this bondage is called liberation, or mokṣa, by both the Yoga and Samkhya schools of Hinduism, and can be attained by insight and self-restraint.

Shakti (Devanagari: शक्ति, IAST: Śakti; lit. 'energy, ability, strength, effort, power, might, capability') in Hinduism, is the "Universal Power" that underlies and sustains all existence. Conceived as feminine in essence, Shakti as devi refers to the personified energy or power of a male deity, often personified as the complementary force of the given Hindu god.

In Tantric Shaktism, Shakti is the foremost deity, akin to Brahman. In Puranic Hinduism, Shiva and Shakti are the masculine and feminine principles that are complementary to each other. The female deity is prakriti, the active, dynamic and creative principle. The male deity is purusha, the passive, unchanging and observing principle. The interaction of both principles is what creates the universe.

Ātman (/ˈɑːtmən/; Sanskrit: आत्मन्) in Hinduism is the true, innermost essence or self of a living being, conceived as eternal and unchanging. Atman is conceptually closely related to the individual self, Jīvātman, which persists across multiple bodies and lifetimes, but different from the self-image or ego (Ahamkara), the emotional aspect of the mind (Citta), and the bodily or natural aspects (prakṛti). The term is often translated as soul, but is better translated as "Self" or essence. To attain moksha (liberation), a human being must acquire self-knowledge (Atma Gyaan or Brahmajnana).

The six orthodox schools of Indian philosophy have different views on what this self is. In Samkhya and Yoga, which call the essence purusha, and in Advaita Vedanta, the essence is pure consciousness or witness-consciousness (sakshi), beyond identification with phenomena. In Samkhya and Yoga there are innumerable selves, while in Advaita Vedanta there is only one Self. Prominent views in Vedanta on the relation between (Jīv)Atman and the supreme Self (Paramātmā) or Ultimate Reality (Vishnu, Shiva, Brahman) are that atman and Brahman are simultaneously different and non-different (Bhedabheda), non-different (Advaita, 'not-two'), different with dependence (Dvaita, 'dualist'), or non-different but with dependence (Vishishtadvaita, qualified non-dualism).

Ahamkara (Sanskrit: अहंकार; Romanized: Ahaṁkāra), "I-making," is a Sanskrit term in Hindu philosophy referring to the construction of a self-concept, or the false identification of the self (Purusha, atman) with impermanent entities such as the body, mind, or material objects. It evolves from Mahat-tattva, and is one of the four Antaḥkaraṇa (functions of the mind).

Ātman (/ˈɑːtmən/; Sanskrit: आत्मन्) in Hinduism is the true, innermost essence or self of a living being, conceived as eternal and unchanging. Atman is conceptually closely related to the individual self, Jīvātman, which persists across multiple bodies and lifetimes, but different from the self-idea or ego (Ahamkara), the emotional aspect of the mind (Citta), and the bodily or natural aspects (prakṛti). The term is often translated as soul, but is better translated as "Self" or essence. To attain moksha (liberation), a human being must acquire self-knowledge (Atmajnana or Brahmajnana).

The six orthodox schools of Indian philosophy have different views on what this self is. In Samkhya and Yoga, which call the essence purusha, and in Advaita Vedanta, the essence is pure consciousness or witness-consciousness (sakshi), beyond identification with phenomena. In Samkhya and Yoga there are innumerable selves, while in Advaita Vedanta there is only one Self. Prominent views in Vedanta on the relation between (Jīv)Atman and the supreme Self (Paramātmā) or Ultimate Reality (Brahman) are that atman and Brahman are simultaneously different and non-different (Bhedabheda), non-different (Advaita, 'not-two'), different with dependence (Dvaita, 'dualist'), or non-different but with dependence (Vishishtadvaita, qualified non-dualism).