Samkhya is the oldest of the orthodox philosophical systems in Hinduism. Samkhya postulates that all in reality is either a soul or matter. There are many souls and they possess consciousness, but they are devoid of all qualities. Matter consists of three dispositions: steadiness, activity, and dullness. Because of the intertwined relationship between the soul and these dispositions, an imbalance in disposition causes the world to evolve. Liberation occurs with the realisation that the soul and the dispositions are different. Samkhya is a dualistic philosophy, but there are differences between Samkhya and other forms of dualism. In the West, dualism is between the mind and the body, whereas in Samkhya it is between the self and matter. The concept of the self is roughly equivalent to the Western concept of the mind. Samkhya was originally not theistic, but in confluence with Yoga it developed a theistic variant.
Yoga is somewhat different from Samkhya. Its primary text is the Bhagavad Gita, which explores the four primary systems: Karma Yoga, Buddhi Yoga, Dhyana Yoga, and Bhakti Yoga. In the Bhagavad Gita itself, Yoga is described as being many millions of years old, and is essentially a universal method of union with the Supreme. For many centuries yoga practitioners have debated about the specific nature of this Supreme (i.e., personal or non-personal), and according to the different traditions describe the Supreme as Brahman, Paramatma, or Bhagavan respectively.
The most significant difference from Samkhya is that Yoga incorporates the concept of a personal god, Ishvara, but also upholds Ishvara as the ideal upon which to meditate. This is either because Ishvara is the only aspect of the soul that has not become entangled with nature, or because Ishvara is the Supreme God himself (depending on one's point of view). Yoga also utilizes the concepts of Brahman and Atman found in the Upanishads, thus breaking from the Samkhya school by adopting concepts of Vedantic monism.
Yoga lays down elaborate prescriptions for gradually obtaining physical and mental control over the personal self. This occurs until one's consciousness becomes aware of one's authentic self, or atman, as distinct from one's feelings, thoughts, and actions. Realisation of the goal of Yoga is known as moksha, nirvana, and samadhi, all of which hold that the atman is of the same quality as the infinite Brahman. Patanjali wrote an influential text on Raja Yoga entitled Yoga Sutra and is often quoted as an authority on the Yoga process.
The Nyaya school is based on the Nyaya Sutras. They were written by Aksapada Gautama, probably in the second century B.C.E. The most important contribution made by this school is its methodology. This methodology is based on a system of logic that has subsequently been adopted by the majority of the Indian schools. This is comparable to the relationship between Western science and philosophy, which was derived largely from Aristotelian logic.
Nevertheless, Nyaya was seen by its followers as more than logical in its own right. They believed that obtaining valid knowledge was the only way to gain release from suffering, and they took great pains to identify valid sources of knowledge and distinguish these from mere false opinions. According to Nyaya, there are exactly four sources of knowledge: perception, inference, comparison, and testimony. Knowledge obtained through each of these is either valid or invalid. Nyaya developed several criteria of validity. In this sense, Nyaya is probably the closest Indian equivalent to analytic philosophy. The later Naiyanikas gave logical proofs for the existence and uniqueness of Ishvara in response to Buddhism, which, at that time, was fundamentally non-theistic. An important later development in Nyaya was the system of Navya-NyÄya.
The Vaisheshika school was founded by Kanada and postulates an atomic pluralism. All objects in the physical universe are reducible to certain types of atoms, and Brahman is regarded as the fundamental force that causes consciousness in these atoms.
Although the Vaisheshika school developed independently from the Nyaya, the two eventually merged because of their closely related metaphysical theories. In its classical form, however, the Vaisheshika school differed from the Nyaya in one crucial respect: where Nyaya accepted four sources of valid knowledge, the Vaisheshika accepted only two—–perception and inference.
The main objective of the Purva Mimamsa school was to establish the authority of the Vedas. Consequently, this school's most valuable contribution to Hinduism was its formulation of the rules of Vedic interpretation. Its adherents believe that one must have unquestionable faith in the Vedas and perform the yajñas, or fire-sacrifices, regularly. They believe in the power of the mantras and yajñas to sustain all the activity of the universe. In keeping with this belief, they place great emphasis on dharma, which consists of the performance of Vedic rituals.
The Mimamsa accepted the logical and philosophical teachings of the other schools, but felt they did not sufficiently emphasize attention to right action. They believed that the other schools of thought that aimed for release (moksha) did not allow for complete freedom from desire and selfishness, because the very striving for liberation stemmed from a simple desire to be free. According to Mimamsa thought, only by acting in accordance with the prescriptions of the Vedas may one attain salvation.
The Mimamsa school later shifted its views and began to teach the doctrines of Brahman and freedom. Its adherents then advocated the release or escape of the soul from its constraints through enlightened activity. Although Mimamsa does not receive much scholarly attention, its influence can be felt in the life of the practising Hindu, because all Hindu ritual, ceremony, and law is influenced by this school.
The Vedanta, or later Mimamsa school, concentrates on the philosophical teachings of the Upanishads rather than the ritualistic injunctions of the Brahmanas.
While the traditional Vedic rituals continued to be practised as meditative and propitiatory rites, a more knowledge-centered understanding began to emerge. These were mystical aspects of Vedic religion that focused on meditation, self-discipline, and spiritual connectivity, more than traditional ritualism.
The more abstruse Vedanta is the essence of the Vedas, as encapsulated in the Upanishads. Vedantic thought drew on Vedic cosmology, hymns and philosophy. The Brihadaranyaka Upanishad appeared as far back as 3,500 years ago. While thirteen or so Upanishads are accepted as principal, over a hundred exist. The most significant contribution of Vedantic thought is the idea that self-consciousness is continuous with and indistinguishable from consciousness of Brahman.
The aphorisms of the Vedanta sutras are presented in a cryptic, poetic style, which allows for a variety of interpretations. Consequently, the Vedanta separated into six sub-schools, each interpreting the texts in its own way and producing its own series of sub-commentaries. Four of them are given here.
Advaita is probably the best-known of all Vedanta schools. Advaita literally means "not two." Its first great consolidator was Adi Shankaracharya (788-820), who continued the line of thought of some of the Upanishadic teachers, and that of his teacher's teacher Gaudapada. By analysing the three states of experience—–waking, dreaming, and deep sleep—–he established the singular reality of Brahman, in which the soul and Brahman are one and the same. Ishvara is the manifestation of Brahman to human minds under the influence of an illusionary power called Avidya.
Teachers who branched away from the Advaitic line of thought accused Adi Shankara of teaching Buddhism while pretending to be a Hindu. Nevertheless, the majority see him as drawing from concepts ingrained in texts pre-dating the Buddha, like the more abstruse sections of the Vedas, and the older Upanishads, several of which are conservatively dated as far back as 1500 B.C.E.
Subsequent Vedantins debated whether Brahman had attributes. The belief that Brahman does have attributes gave rise to a proliferation of devotional attitudes and more widespread worship of Vishnu and Shiva. Advaita Vedanta, however, is strictly grounded in the thought that Brahman does not have attributes. The Vishistadvaita and Dvaita schools, in contrast, hold that Brahman does have attributes.
Ramanujacharya (1040-1137) was the foremost proponent of the concept of Brahman having a definite form, name, and attributes. He saw Vishnu as Brahman. He taught that reality had three aspects: Vishnu, soul, and matter. Vishnu is the only independent reality, while souls and matter are dependent on Vishnu for their existence. Thus, Ramanuja's system is known as qualified non-dualism.
Like Ramanuja, Madhvacharya (1218-1317) identified Brahman with Vishnu, but his view of reality was pluralistic. According to Dvaita, there are three ultimate realities: Vishnu, soul, and matter. Five distinctions are made: (1) Vishnu is distinct from souls; (2) Vishnu is distinct from matter; (3) Souls are distinct from matter; (4) A soul is distinct from another soul, and (5) Matter is distinct from other matter. Souls are eternal and are dependent upon the will of Vishnu. This theology attempts to addresses the problem of evil with the idea that souls are not created.
Dvaitadvaita was proposed by Nimbarka, a 13th century Vaishnava Philosopher from the Andhra region. According to this philosophy there are three categories of existence: Brahman, soul, and matter. Soul and matter are different from Brahman in that they have attributes and capacities different from Brahman. Brahman exists independently, while soul and matter are dependent. Thus soul and matter have an existence that is separate yet dependent. Further, Brahman is a controller, soul an enjoyer, and matter the thing enjoyed. Also, the highest object of worship is Krishna and his consort Radha, attended by thousands of gopis, or cowherdesses; of the celestial Vrindavana; and devotion consists in self-surrender.
Chaitanya Mahaprabhu (1486-1534), a devotee of Krishna, proposed a synthesis between the monist and dualist philosophies by stating that the soul is both distinct and non-distinct from God, whom he identified as Krishna, and that this, although unthinkable, may be experienced through a process of loving devotion (bhakti). This philosophy of "inconceivable oneness and difference" is followed by a number of modern Gaudiya Vaishnava movements, including ISKCON, sometimes called the Hare Krishna movement. ISKCON has recently participated in bringing the academic study of Krishna-related philosophies into Western academia through the theological discourse on Krishnology.
Akhilananda, Swami ( )Hindu Psychology: Its Meaning for the West. Routledge
The six volume Psychology and Religion set of the International Library of Psychology explores the interface between psychology and religion, looking at aspects of religious belief and mysticism as related to the study of human consciousness. Hindu Psychology looks at the relevance of Hindu belief systems and theories of perception for the West.ISBN 0203002660 ebook