Tripura Rahasya

Sage Dattatreya said,

The Sage's Son continued,

• That consciousness which illumines the 'exterior' is called Sivatattva, whereas the individual feeling as 'I' is Saktitattva.
• When the awareness of the exterior, combined with the 'I', encompasses the entire imagined space as 'I', it is called the Sada-Siva-tattva.
• When, later, discarding the abstraction of the Self and the exterior, clear identification with the insentient space takes place, it is called Ishwara tattva. The investigation of the last two steps is pure vidya (knowledge).
• All these five tattvas are pure because they relate to an as-yet-undifferentiated condition, like potentialities in a seed.
• After the differentiation is made manifest by will-force the insentient part predominates over the other, as opposed to the contrary condition before. 
• That insentient predominance is called Maya Sakti, after differentiation is clearly established, like the sprout from a seed.
• The sentient phase now contracts, being relegated to a minor position and takes on the name of Purusha, being covered by five sheaths, namely kala (something of doership), vidya (some knowledge), raga (desire), kala (time-allotted life) and niyati (fixed order of things).
• Anamnesis of individuals made up of the proclivities acquired as a result of engaging in diverse actions in previous births, is now supported by intelligence and remains as prakriti.
• This prakriti is tripartite because the fruits of actions are of three kinds: She manifests as the three states of life, wakefulness, dream and deep sleep. She then assumes the name, chitta (mind).
• The anamnesis goes by the name of prakriti in dreamless slumber, and chitta in the other states. It is always comprised of the insentient phase of the proclivities of the mind and the sentient phase of intelligence.