When the Buddha first started teaching the Dharma,he began by teaching the Avatamsaka Sutra,which is known as the king of all Buddhist sutras.He talked about the 80 scrolls of this sutra for twenty-one days.Then he turned on to the Agamas for twelve years,which is on early or primitive Buddhism.Then he turned to the Mahayana Sutras,which are known as the Vaipulya Sutras,such as the Amitabha Sutra,or the Vimalakirti Sutra and so on for eight years.After that,he then spent the next twenty-two years talking about the sutras on Prajna Wisdom.Therefore,from this we can see how important Prajna is in Buddhism.
When we talk about Prajna,it is not about knowledge,nor our learnings from schools,nor is it a type of philosophy. Instead,it is a theory about our true self.But at the same time when we talk about this true self or Prajna,it is formless and therefore,while we may see what others look like in our normal lives,we usually fail to be able to find our true appearance.And now this true self is formless and shapeless,it would take a lot of learning and hard work in order for us to find the so-called Prajna.
When Master Hui Neng,the sixth patriarch of Zen School taught the Dharma,he once asked his audience a very special question.He said,"Now,I have a thing in mind.But this thing is either without a head or a tail,nor is it with hands,legs or arms,nor does it have a face or a backside.And can you tell me what this thing is?"
There was a very confident youngster among the audience he stood up and said,"I know the answer.This thing that you are talking about is the origin of all the Buddhas,which is the Buddha Nature within all sentient beings."