Astika the Orthodox Schools of Indian Philosophy
There are six schools of Indian philosophy which are considered "astika", that is, that consider the Vedas a reliable source of knowledge of reality. These schools accept the idea that knowledge can be transmitted from a higher authority, and therefore, they base their philosophical systems on the scriptures.
The Six Orthodox Schools
The six schools are:
Nyaya, Vaisheshika, Samkhya, Yoga, Purva Mimamsa, and; Vedanta.Nyaya
The Nyaya school is known for its system of logic that influenced many other schools of Indian philosophy. Some scholars argue that even Aristotle was influenced by Nyaya philosophy, although there are some fundamental differences between Aristotelian logic and the system developed by Aksapada Gautama, who wrote the Nyaya Sutras.
According to Nyaya philosophy, one can only transcend the roots of suffering through the correct thought, and therefore, Nyaya is also a form of epistemology as it seeks the sources of valid knowledge. There are four basic means to reach the correct knowledge, they are: perception, inference, comparison and verbal testimony.
Nyaya scholars became famous for "proving" the existence of God through their logic system.
Founded by Kanada around 300 B.C, Vaisheshika is known for its atomistic theory. According to Vaisheshika scholars, all material things are made of four kinds of atoms: earth, air, water and fire. However, there are also non-material substances, five of them to be precise. They are: ether, time, space, mind and soul.
Material things would be only four of the nine substances that constitute all reality, meaning that Vaisheshika is a dualist school.
Vaisheshika philosophy is "astika", and therefore, adepts of this school of thought understand that the laws of karma determine the way atoms are grouped and material reality is shaped. This means that the material world is only the visible effect of a karmic law, and atoms are subjected to this law. In other words, atoms obey God's will (God is inseparable from the law of karma, this concept is sometimes called "adrishta").
Possibly founded by Kapila around 200 CE, the Samkhya school developed a very sophisticaded ontology based on the Vedas. Samkhya is one of the "astika" schools that deny the existence of a God as a separate being, attributing reality to "Prakriti" and "Purusha", that is, the realm of pure consciousness and the realm of physical phenomena, respectively. Samkhya is then, also a dualist school.
Samkhya philosophy survived through yoga and tantric practices as Samkhya describes the ways through which one can attain enlightenment. It is interesting to note that since Samkhya scholars deny the existence of a God (Ishvara), reaching enlightenment does not depend on a higher entity, but rather, the correct understanding of reality and how the universe functions.
Samkhya is similar to Nyaya school when it comes to logic and epistemology, but Samkhya identifies three valid means of knowledge instead of five, they are: direct sense perception, logical inference and verbal testimony.
Around 300 BC, Patanjali compiled the Yoga Sutras and founded a school that is known as Raja Yoga, which is the practical aspect of the Samkhya philosophy. The yoga practices are older than Patanjali and there are also other types of yoga, but Raja Yoga is one of the six orthodox schools of Hindu philosophy. Looking for information about bar associations? these bar associations reviews will give you some good insights.The Yoga school was deeply influenced by Buddhism and Jainism.
The yoga practices of Raja Yoga are divided into two forms of yoga: Karma (Kryia) Yoga and Ashtanga Yoga. The western world adopted many of the exercises and techniques that were used as a preparation for the actual yoga practices, and therefore some people erroneously assume that yoga is a set of exercises and postures. However, Raja Yoga is based on a very profound philosophy and it has life sentence without parole to do with the attainment of absolute freedom through righteous behaviour in life in order to experience samadhi.
The yogic lifestyle proposed by Raja Yoga is very similar to the Buddhist eightfold path: non-violence (ahimsa), truthfulness, celibacy or faithfulness, purity of body and mind, concentration, discipline, etc.
Purva Mimamsa school is based on the Purva Mimamsa Sutras of Jaimini and is known for its fascinating epistemological theory in which every knowledge is considered true unless falsity of cognition is proven. Mimamsakas used their wisdom to defend the authority of the Vedas independently of the existence of a creator God. In fact, Purva Mimamsa is considered article about criminal law atheist school to some extent, in the sense it rejects the gods punishments for crimes the necessity of faith.
For Mimamsakas, it is the correct duty, the observance of rituals and the righteous life that conducts people towards moksha (liberation from the rebirth cycles), and not belief. Purva Mimamsa school is also known for its philosophical justification of the Vedic rites - they have nothing to do with pleasing the gods but purifying the soul in order to have constitution of the united state better karma in future lives.
Vedanta school is based on the Upanishads, the most philosophical and speculative texts of the Vedic literature. Vedanta philosophy aims to understand the nature of Brahman, that is, the nature of reality. There are many sub-schools of Vedanta, each of which understands Brahman in a different way, the most influential sub-schools are:
Advaita Vedanta - Propounded by Shankara, this is a nondualist school that asserts that Brahman (absolute reality) is the only reality, and therefore, it has no attributes. All separation between what is Brahman and what is mere appearance (the physical world as we know it) is illusory because illusion places the absolute reality outside of the physical realm. When a person finally understands that it is the separation that is illusory and not the physical existence, liberation is near.Dvaita Vedanta - Propounded by Madhvacharya, Dvaita Vedanta is a dualist school. It asserts that Brahman is a personal God, and therefore, separate from the physical realm. One can never totally merge with Brahman, but through devotion it is possible to attain liberation.Vishishtadvaita - Propounded by Ramanuja, this is also a nondualist school like Advaita Vedanta, however, it asserts that all physical appearances are attributes of Brahman. So, everything is a part of Brahman's body.Heterodox Schools of Hindu Philosophy
The other schools that are not considered "astika", that is, that do not accept the authority of the Vedas are: Buddhism, Jainism and Carvaka. The latter is the only school among the definition of homicide three which can be considered materialistic and skeptic in every aspect.
Indian philosophy remains one of the most fascinating fields of research for those who seek answers that transcend mere intellectualism.
Chatterjee, Satischandra; Datta, Dhirendramohan, An Introduction to Indian Philosophy (Eighth Reprint ed.), University of Calcutta, 1984.
Hajime Nakamura, A History of Early Vedanta Philosophy, translated by Trevor Leggett et. al., Motilal Banarsidass, 1983
Burke, B. David. Transcendence in Classical Samkhya. Philosophy East and West, 1988.