Sankhya is one of the six classical schools of Indian philosophy and the philosophical foundation on which the practical system of yoga rests. The word comes from samyag akhyate, meaning “that which explains the whole.” And indeed, Sankhya offers a comprehensive account of reality, from the most subtle and undifferentiated to the most gross and particular, providing the map through which the practice of yoga’s navigation is understood.
Purusha and Prakriti
The organizing principle of Sankhya is a distinction between two fundamental realities: Purusha and Prakriti. Purusha is pure consciousness, untainted, ever-pure, self-existent, without qualities or modifications, simply the witness. Prakriti is primordial, unmanifest matter: not physical matter in the ordinary sense, but the subtlest possible substrate from which all material existence, including the human mind, the senses, and the five elements, ultimately emerges. Purusha and Prakriti are the two permanent realities in the Sankhya system; everything else is a product of their interaction.
In the state of liberation described by both Sankhya and yoga, Purusha is recognized as having always been independent of Prakriti. But in the ordinary, unawakened human being, consciousness has become so entangled with the products of Prakriti, with the body, the senses, the ego, the mind, that it can no longer perceive its own nature clearly. Sankhya explains the mechanism of this entanglement, and yoga provides the means of disentangling.
The Three Gunas
Prakriti is characterized by three fundamental qualities, the gunas: sattvas (lightness, clarity, purity), rajas (activity, restlessness, stimulation), and tamas (heaviness, inertia, dullness). These three qualities combine and recombine in endless proportions to produce every aspect of manifest existence. When sattvas dominates, the mind is clear and the practitioner can perceive subtle realities. When rajas dominates, the mind is busy and agitated. When tamas dominates, the mind is heavy and dull. The practice of yoga, including ethical practice, regulated lifestyle, and meditation, is in part the cultivation of sattvas, not as an end in itself but as the condition under which the final discrimination between Purusha and Prakriti becomes possible.
The Evolutes of Prakriti
From Prakriti, the first evolute to emerge is mahat or buddhi, the cosmic intelligence, individuated as buddhi in each person. Buddhi is the faculty of discernment, the highest function of the individual mind. From buddhi emerges ahamkara, the ego or I-maker, the principle by which consciousness begins to take on the identity “I am this or that.” From ahamkara emerge manas (the lower, sensory mind), the ten indriyas (the five cognitive senses and the five instruments of action), and the five subtle elements (tanmatras), which in turn condense into the five gross physical elements: earth, water, fire, air, and space.
The significance of this map for practice is that the entire structure of the human being, from the grossest physical body to the subtlest faculty of discernment, is Prakriti. Only Purusha, pure consciousness, stands outside the system. The process of meditation is, in Sankhya terms, a process of retracing: moving attention systematically inward through the layers of Prakriti, from the gross to the subtle to the subtlest, until the practitioner arrives at the level of buddhi standing alone, and finally at the recognition of Purusha as distinct from everything that buddhi is not.
Sankhya and Yoga Together
This is why the sage Vyasa describes yoga as Sankhya-Yoga: the practical methods of yoga rest on the philosophical foundation of Sankhya. Without Sankhya’s map, the practitioner meditates without knowing where they are in the territory. Without yoga’s methods, Sankhya remains an intellectual map never actually traversed. Together, they constitute a complete science of consciousness: a map and the means to walk it.
The tradition is careful to note that practitioners do not need to master Sankhya philosophy before beginning to practice. The principles can be understood gradually, built up over time as practice deepens. What matters most in the beginning is an intuitive grasp of the fundamental distinction: there is that which changes, experience, sensation, thought, emotion, and there is that which observes those changes without itself being changed. Everything else in Sankhya is a refinement of that basic distinction, and that distinction is already available to anyone who has ever watched their thoughts in meditation and noticed that the watcher and the thought are not the same thing.
