After the five mahabhutas (great elements), the five tanmatras (subtle elements), the five karmendriyas (organs of action), and the five jnanendriyas (organs of cognition or sensing), come the three antahkaranas (internal organs). The antahkaranas are manas (mind), buddhih (intellect/intuition), and ahamkara (ego, sense of self as an individual). These 23 tattvas describe the objective world and our place in it as manifest physical beings and as beings who sense and think about our place in the physical world.
The next two tattvas are more in the subjective realm: purusha (nature) and prakriti. In the classical system, the 23 described above plus purusha and prakriti are the sum of the tattvas. In that system, prakriti, is interpreted as “spirit.” It is not the world spirit or the transcendent spirit, but more our individual spirit. Nature is divided from spirit and all of the objective world and individual spirit are different from “Atman” or “Brahma” what is real. In Kashmir Shaivism, there are another 11 tattvas — the six kanchukas (cloakings or coverings) and the five suddha tattvas (pure elements) that describe the relationship between the individualized, diverse, perceptible and perceiving realm, and the purely universal.
Purusha (nature) is a name or way of looking at the 23 earlier described tattvas and prakriti describes the sense we have of there being something more that is unifying and universal among all that is manifest, but still from the perspective of our own individual perception. When we look at nature (purusha) from a more universal perspective, we look at it from how it behaves generally, how it moves, and what moves it, as we look at the laws of nature of physics. In yoga, nature is described from the perspective of the three gunas — tamas, rajas, and sattva.
Tamas is dark, dormant, inert, and heavy. Rajas is fiery, energetic, and impassioned. Sattva is pure, clear, and light. From a classical perspective, tamas is a state we need to transcend to connect to spirit, rajas is the motivating energy that helps us move past tamas to a sattvic state. From the tantric perspective that underlies the Anusara principles, we recognize that tamasic qualities are part of nature and we embrace it where it leads us to a place of balance. At night, for example, it is better to be still and dark for optimal sleep. In this latititude, gardens need a period of dormancy in winter to thrive. When we are sick or exhausted, restorative postures may be more healing and balancing than would be power flow or even meditation. When tamas is out of balance, though, we are sluggish and slothful. We can be stuck in our ways — ways that are unhealthy for ourselves or the planet. We then need to cultivate more rajas. We use fire and passion to transform, to find new ideas, to shift our behavior, to find discipline. If our bodies are weak or inflexible, rajas helps us activate our practice to build power. The rains and warmth of spring make the garden grow. From this perspective, being light and pure based on particular dietary and behavioral strictures is not necessarily the ideal. Rather being sattvic is being in optimal balance; it is knowing ourselves well enough to know when darkness, earthiness, and stillness or light, activity, and “spiritual” practices best serve ourselves, other beings, and the earth. Being sattvic is being clear enough in the multi-faceted relationship between the world around us and our own mind, body, and spirit that our sense of spirit in all things and ourselves is unsullied, and illuminated.