Understanding (Buddhism) [2]

On the Path of Purification of Hinayana Buddhism, understanding is insight knowledge associated with profitable consciousness or moral thought. It is knowing in a way which is more penetrating than perception or consciousness, which are nevertheless included in panna. As well as knowing the object, penetrating its characteristics, it also, through endeavour, brings about manifestation of the path. Although not always present when perception and consciousness are present, it is always accompanied by perception and consciousness. Its proximate cause is concentration.

The "soil" of understanding are all the aggregates, sense-organs or bases, elements, faculties, truths, dependent origination. In this soil are the roots of purification of virtue (purity of morality) and purification of consciousness (purity of mind). From these roots grow the body or trunk of the other five purifications or purities: view; overcoming of doubt; knowledge and vision of what is and what is not the path (discernment of right path and wrong path); knowledge and vision of the way (discernment of the middle way); knowledge and vision (discernment). One who is perfecting his understanding should study these things.

Understanding is considered as of one kind (monad), of two kinds (dyads), of three kinds (triads) or of four kinds (tetrads). There are five dyads, four triads and two tetrads. All have the characteristic of penetrating the individual essences or true nature of states (monad).