Samyavastha or equilibrium is a state in which all forces acting in various directions are balanced perfectly in relation to each other. Such a state is ascribed in Samkhya philosophy to mulaprakriti (primordial nature). It is constituted by three gunas (basic qualities), namely, sattva, rajas and tamas. They have basic specific tendencies very different from each other.
For example, sattva guna indicates lightness, whiteness, wholesomeness, bliss, satisfaction, knowledge, understanding, smoothness, etc. Rajas guna makes for activity, excitement, sharpness, uneasiness, instability and so on. Tamas guna brings about darkness, inertness, heaviness, ignorance, laziness, misery, dejection and the like.
But in the state of mulaprakriti, before the beginning of creation, these three gunas are in a perfectly balanced state, none of them taking the upper hand or dominating and suppressing the other two. The result of balanced forces makes for stability, balance, perfect peace and complete stoppage of movement or action in any direction. This is called the state of trigunasamyavastha. If this state had lasted indefinitely, and there was no change in it, then creation would have been impossible. But that is not the case, because this state of original peace and balance is disturbed due to the proximity of purusha and the inherent dynamism of the gunas and so the samyavastha gives way to the gunakasobhini state in which sattva guna gains the upper hand and the first evolute of prakriti – mahat or buddhi manifests itself. That sparks the beginning of creation, called sarga or srishti. Cycles of evolution and involution continue indefinitely.