Prajna is an essential part of Buddhadharma. Shakymuni Buddha said that even if one practices all the principles of enlightenment, without the guidance of prajna, one is really not practicing Buddhadharma. For example, when you uphold the precepts or practice generosity without prajna, you are really only cultivating merit, which allows you to receive good retribution, such as being reborn in the human realm. Also, cultivating samadhi without prajna, you may experience the dhyana heavens, but once this samadhi is gone you will come back to the world in the same state as before.

To achieve wisdom you need to be guided by correct prajna. What is correct prajna? In the agamas, the early Buddhist scriptures, the Buddha said, "This arises therefore that arises; this perishes, therefore that perishes." The Buddha meant that when ignorance and vexation arise, we do certain deeds, and then we receive the retribution from those deeds. In receiving retribution our vexation causes us to commit more deeds, prolonging this long chain of suffering, which is ultimately the chain of birth and death. This is the meaning of "This arises, therefore that arises."

What does "This perishes, therefore that perishes" mean? Ignorance is the root cause of our vexations. When ignorance perishes, all vexations in the rest of the chain perish. Therefore, as one practices towards enlightenment and ignorance is eliminated, the suffering of birth, old age, sickness and death also perish, along with worry, sorrow, agony, and emotional affliction.

Way of Looking at Prajna