Sāṃkhya is referred to by many as the oldest philosophical system of India. Some of Sāṃkhya’s key concepts are first mentioned in the earliest of the Vedas, however the reality of oral tradition in India suggests that Sāṃkhyan ideas are in fact much older than the Vedas in their written form.
Sāṃkhya is one of the six darśanas (darśana = “way of seeing,” “philosophy”) of Hinduism. Scholars debate that Sāṃkhya, as a system, was not codified until sometime prior to the composition of the Sāṃkhya-kārikā of Iśvarakṛṣṇa in 300-400 A.D. However, the basic elements of Sāṃkhya are found in almost all aspects of the Hindu tradition.
The Sāṃkhya system of Iśvarakṛṣṇa is referred to as “Classical Sāṃkhya.” It is derived from the classical system that emerged historically alongside the Yoga Sūtras of Patañjali and is integral to an understanding of the classical yoga system. Sāṃkhya and Patañjali’s Yoga Sūtras share the same metaphysics, that is, they have the same fundamental understanding of reality, though they differ in the methods that each prescribe to attain liberation. In essence, Sāṃkhya emphasizes rational thinking and analysis, while yoga emphasizes action and experience. Yet, most scholars agree that it would be virtually impossible to understand Patañjali’s Yoga Sūtras without a basic grasp of Sāṃkhyan philosophy.
Sāṃkhya grounds its teachings in the fact of suffering (duḥkha) and the means by which one can liberate him or herself from the condition of duḥkha. As such, the Sāṃkhya is a soteriology — a religious method of salvation. But “religious” here shouldn’t be taken too far; this is not a theistic system. In fact, some have gone so far as to call the Sāṃkhya an “atheist spirituality,” although to others this is a controversial position.
Sāṃkhya is a dualistic system, but the dualism found here is not the familiar dualism of mind/body, soul/world or thought/extension that we find in the Western tradition. The dualism of the Sāṃkhya is one between puruṣa and prakṛti: pure, contentless consciousness, on the one hand, and the contents of consciousness (or non-conscious substance-energy), on the other hand.
Knowledge (jñāna) of the distinction between these two principles is at the heart of the soteriology of the Sāṃkhya. Sāṃkhya is often translated as “enumeration” and refers to the numbering of the 25 tattvas, or principles of reality. 24 of these tattvas are associated with prakṛti, while the 25th tattva, puruṣa, stands metaphysically separate from the tides and turnings of prakṛti.
The practice of Sāṃkhya, then, is a practice of acquiring knowledge by discerning the difference between the manifest (vyakta), the unmanifest (avyakta) and the knower (jña) or seer of the manifest and unmanifest forms of prakṛti. This “knowledge,” however, is no mere intellectual or discursive knowledge, but is an intuitive, meditative knowledge cultivated through deep and sustained contemplative practice.