Egoity or perspective requires some mode of action, and all action involves the gunas, which belong exclusively to prakriti. Consciousness, purusha, is mere presence, sakshitva, without action, dynamics or content. Thus it is said that purusha is unique in that it is neither generated nor generating, whereas all other tattvas are either generating, generated or both. In this view, mind is material. Given its capacity for awareness, it can intuit the presence of purusha, but it is not that purusha.
All mental functions are part of the complex activity of prakriti.
Consciousness is bare subjectivity without a shadow of objective content, and it cannot be said to have goals, desires or intentions. Unlike the Vedantin atman, however, it cannot also be said to be ananda, bliss, for purusha is the pure witness, sakshi, with no causal connection to or participation in prakriti. Yet it is necessary, for the gunas could not be said to be active save in the presence of some principle of sentience. Without purusha there could be no prakriti. Rather, it is closer to the recognition grounded in Newtonian mechanics that, should the universe achieve a condition of total entropy, it could not be said to exist, for there would be no possibility of differentiation in it.