[5][6][7][8][9] Indian philosophy during the ancient and medieval periods also yielded philosophical systems that share concepts with the āstika traditions but reject the Vedas.
[6] The various sibling traditions included in Indian philosophies are diverse and are united by: shared history and concepts, textual resources, ontological and soteriological focus, and cosmology.
[21] Ancient and medieval Hindu texts identify six pramāṇas as correct means of accurate knowledge and truths: Each of these are further categorised in terms of conditionality, completeness, confidence and possibility of error, by the different schools.
[57] This fusion, state the Samkhya scholars, led to the emergence of buddhi (awareness, intellect) and ahankara (individualised ego consciousness, "I-maker").
[63][64][65][66] The Samkhya karika, one of the key texts of this school of Hindu philosophy, opens by stating its goal to be "three[67] kinds of human suffering" and means to prevent them.
– Verse 1 The Guṇas (qualities) respectively consist in pleasure, pain and dullness, are adapted to manifestation, activity and restraint; mutually domineer, rest on each other, produce each other, consort together, and are reciprocally present.
– Verse 17 The soteriology in Samkhya aims at the realisation of Puruṣa as distinct from Prakriti; this knowledge of the Self is held to end transmigration and lead to absolute freedom (kaivalya).
[81][82][83] Like Advaita Vedanta, the Yoga school of Hindu philosophy holds that liberation/freedom in this life is achievable, and that this occurs when an individual fully understands and realises the equivalence of Atman (Self) and Brahman.
The Supreme Good results from knowledge, produced from a particular dharma, of the essence of the Predicables, Substance, Attribute, Action, Genus, Species and Combination, by means of their resemblances and differences.
[52][92] Vaiśeṣika metaphysical premises are founded on a form of atomism, that reality is composed of four substances (earth, water, air, and fire).
An atom is, according to Vaiśeṣika scholars, that which is indestructible (anitya), indivisible, and has a special kind of dimension, called "small" (aṇu).
[86] The Vaiśeṣikas stated that size, form, truths and everything that human beings experience as a whole is a function of atoms, their number and their spatial arrangements, their guṇa (quality), karma (activity), sāmānya (commonness), viśeṣa (particularity) and amavāya (inherence, inseparable connectedness of everything).
This premise led Nyāya to concern itself with epistemology, that is, the reliable means to gain correct knowledge and to remove wrong notions.
[99][50] The Kumārila Bhaṭṭa sub-school of Mīmāṃsā added a sixth way of knowing to its canon of reliable epistemology: anupalabdi (non-perception, negative/cognitive proof).
Rather, it held that the Self (Atma) is an eternal, omnipresent, inherently active spiritual essence, then focussed on the epistemology and metaphysics of dharma.
They considered the Upanishads and other texts related to self-knowledge and spirituality to be of secondary importance, a philosophical view that the Vedanta school disagreed with.
[30] Mīmāṃsākas considered orderly, law-driven, procedural life as the central purpose and noblest necessity of dharma and society, and divine (theistic) sustenance means to that end.
The epistemology of the Vedantins included, depending on the sub-school, five or six methods as proper and reliable means of gaining any form of knowledge:[92] pratyakṣa (perception), anumāṇa (inference), upamāṇa (comparison and analogy), arthāpatti (postulation, derivation from circumstances), anupalabdi (non-perception, negative/cognitive proof) and śabda (word, testimony of past or present reliable experts).
Consequently, the Vedanta separated into many sub-schools, ranging from theistic dualism to non-theistic monism, each interpreting the texts in its own way and producing its own series of sub-commentaries.
[126][125] Some believe that Shankara is a "closet Buddhist," suggesting as evidence his positions that selfhood is illusory and an experience of it disappears after one attains enlightenment.
[128] The Dvaita Vedanta school believes that God (Vishnu, Paramatman) and the individual Selfs (Atman) (jīvātman) exist as independent realities, and these are distinct.
[132] The distinguishing factor of Dvaita philosophy, as opposed to monistic Advaita Vedanta, is that God takes on a personal role and is seen as a real eternal entity that governs and controls the universe.
[133] Like Vishishtadvaita Vedanta sub-school, Dvaita philosophy also embraced Vaishnavism, with the metaphysical concept of Brahman in the Vedas identified with Vishnu and the one and only Supreme Being.
Also, the highest object of worship is Krishna and his consort Radha, attended by thousands of gopis; of the Vrindavan; and devotion consists in self-surrender.
[141][142][143] In accordance with the Vishnu Purana, this sub-school ascribes six virtues to God (Bhagavan): power (aishvarya), potency (virya), fame (yasha), prosperity (shri), knowledge (jnana), and renunciation (vairagya).
The potency of Bhagavan, which is transcendental, is not conceivable to humans and its relationship to Bhagwan is characterised as one in which there is "inconceivable difference in non-difference" (acintya-bhedabheda).
[145][15][146] It rejects supernaturalism, emphasises materialism and philosophical skepticism, holding empiricism, perception and conditional inference as the proper source of knowledge[147][148] Cārvāka is an atheistic school of thought.
[153] One of the widely studied principles of Cārvāka philosophy was its rejection of inference as a means to establish valid, universal knowledge, and metaphysical truths.
[167] This tradition later merged with the Tamil Saiva movement and expression of concepts of Shaiva Siddhanta can be seen in the bhakti poetry of the Nayanars.
[176] This implies that from the point of view of Kashmir Shavisim, the phenomenal world (Śakti) is real, and it exists and has its being in Consciousness (Chit).