Humankind has always pondered existence: “What is this life all about? Who am I? Is there a God? What is the meaning of life? Can I be at peace? What is freedom? Why is there so much inequality and misery in this world? What is reality?” Such enquiry is called philosophy. Though the word philosophy may sound abstract, the fact is that we all live by our philosophy, whether we know it or not. Even someone who lives an amoral or unscrupulous life has a philosophy: “My needs must be met no matter what happens to others”—a very simplistic ideology!

In India philosophical enquiry has been pursued for millennia. While the human capacity for thought, speculation, and experience is no better today, we have better tools to help us with enquiry. Each of India’s eight major schools of philosophy is popularly classified as either theistic and atheistic, which simply indicates whether or not that system is based on the four Vedas, which are considered the scriptures of India. A system that accepts the Vedas as a source of knowledge is deemed theistic, or orthodox; a system that does not accept Veda is called atheistic, or heterodox. I prefer the terms orthodox and heterodox, since theistic implies a belief in God, which doesn’t always apply. One influential Vedic philosophical system, for example, does not incorporate a belief in God.

Every philosophy has two aspects: metaphysics and epistemology. The first deals with nature of reality, existence, and experience, while the second is centered on how we know things, on the means of knowledge (pramāṇa). The goal of Indian philosophies is to help the human being become free from the sense of limitation. Freedom, liberation, nirvāna, satori, mokṣa, kaivalya, Buddhahood—all are but names that point to the same end. Being fundamentally goal-oriented, Indian philosophies are therefore not armchair speculations, but self-contained, practical means that enable anyone to gain freedom from limitation.

While it may appear as though the different systems are butting heads with each other—which is true if one studies advanced texts of these systems—such debates are simply a method for better understanding and for addressing doubts about a chosen path of philosophical pursuit. At the goal level and the basic means level (sädhana, or practice), all Indian philosophies are identical, and all practitioners can therefore benefit, no matter what the theoretical differences might be. While we do not need to ignore these differences, we also do not need to be judgmental or dogmatic about them.

Of India’s eight major philosophical systems, six are orthodox (Nyāya, Vaiśeṣika, Sāṅkhya, Mīmāmsa, Yoga, and Vedānta) and two are heterodox (Buddhism and Jainism). Yoga and Vedānta are also theistic, as we understand the word theism. Although Yoga and Vedānta are both orthodox and theistic systems, they vary in terms of both epistemology and metaphysics.

Epistemological Differences: Yoga accepts three sources or means of knowledge: direct perception, inference, and the Vedas, though the pursuit of Yoga proceeds independent of Vedas. Vedānta (which literally means “the end portion of the Vedas,” which is called the Upaniṣads) accepts six means of knowledge: direct perception, inference, presumption, illustration, noncognition, and the Vedas, though the pursuit of Vedānta depends primarily on the Upaniṣads, with the other sources being considered secondary, if not just supportive of the vision rendered in the Upaniṣads.

Metaphysical Differences: Yoga postulates infinite number of puruṣas and one prakŗti. Puruṣa and prakŗti are totally unconnected with each other. Whereas puruṣa represents the nature of awareness, prakŗti is inert and incapable of awareness, consciousness, or knowledge. Prakŗti is composed of three guṇas (qualities): sattva (clarity), rajas (activity), and tamas (stupor). Before creation, the guṇas exist in balance with each other; in fact, creation occurs precisely by disturbing the balance among them. God is considered to be a super-puruṣa that remains unassociated with prakŗti. Human bondage arises from ignorance of the fact that one’s individual soul, the puruṣa, is essentially unconnected to the body-mind complex, the prakŗti, and the tendency therefore to associate oneself with the latter. In Yoga, then, freedom occurs through a methodical process of disassociation, as described in Patanjali’s yoga aphorisms. Kaivalya is the experiential state of the free nature of the puruṣa.

Vedānta, on the other hand, postulates a single, nondual (advaita) Being, which is called Brahman (etymologically, the word means “bigness” or “limitlessness”). Brahman is pure existence, an awareness that is fullness. God, world, and individual seeker are one. However, the seeker’s perception may be overwhelmed by the challenges of the manifest world, though they are not real but only apparent. The duality between world and God, between living and being is explained via the concept māyā, a widely misunderstood term that is often translated as “illusion,” but which actually means “is not what appears.” The difference between God and the individual is that God controls māyā, while the individual is controlled by māyā. While Vedānta’s reputation has been damaged by wrongful use of the world illusion, Vedānta’s true goal is to appreciate the reality that one is essentially and inherently free and limitless. The ability to sustain this nondual vision despite living within the perception of duality is called wisdom or freedom. Because appreciation of nonduality is a cognitive process, not the result of doing, Vedānta practitioners focus on scriptural study, reflection, and contemplation.

But when one is stuck in ignorance and buffeted by the world, how does one come to appreciate the Truth? It is in the process of untangling oneself, the sādhana, where Vedānta and Yoga share similarities. Both systems talk about yama, niyama, viveka, vairāgya, the development of compassion, love, forgiveness, humility, and so on. And because the sādhana of Yoga so closely resembles the sādhana of Vedānta, the commentator to Yoga aphorisms is Vyāsa, who also wrote a set of aphorisms on Vedānta.

There is much confusion about Vedānta: one calls to mind not only Śaṅkara’s Advaita Vedānta, but also Rāmānuja’s Viśiṣṭādvaita Vedanta, Madhva’s Dvaita Vedānta, and even the Vedāntas that pre-date that of Śaṅkara. My area of expertise, however, is in Advaita Vedānta, which is what I explore in this blog.

For more detailed information, see Satischandra Chatterjee and Dhirendramohan Datta, An Introduction to Indian Philosophy (1968), http://www.amazon.com/Introduction-Indian-Philosophy-Chatterjee/dp/8129111950.