The teaching methodology
Why is there a need for a specific method of teaching? Because we are not speaking about a system of philosophy that just needs to be clearly presented with a definition of the main concepts and its underlying assumptions. We are also not speaking about a simple descriptive theory which needs to be experienced and validated by an action like meditation.
We are speaking about a means of knowledge revealing and unfolding the reality as it is. Therefore, it should have a method to make one understand this reality. We have seen in the previous section how the inherent limitations of the language can be overcome by using the words with their implied meaning to reveal the nature of the reality. Let us now explore this subject further and see this method by which the Upanishads unfold its vision.
Vedanta employs extensively negative sentences (neti, neti, which means not this, not this),to indicate the nature of reality. Since "I" is revealed to be the truth of the universe, Vedanta has to negate all what we take ourselves to be. It also negates that any object in the universe known through ones perception or inference can be the ultimate reality.
Since it is not sufficient to only negate what the reality is not, the Upanishads gives also a positive revelation by using defining words as satyam, existence and jnanam, consciousness with their implied meaning. Various examples, analogies, imageries or models are also used by the Upanishads. For example, in KathaUpanishad, an analogy of a chariot is used to reveal the nature of I. This is done through equating the chariot to the body, mind to the reins, intellect to the driver of the chariot and the owner of the chariot to I. The idea is to indicate that 'I' am totally independent of body, mind, and intellect. Other analogies are used such as an imagery of light in Brhadaranyaka Upanishad and in the Gita, fire/sparks and spokes/hub of a wheel in MundakaUpanishad, five elements model of creation in Taittriya Upanishad, imagery of the banyan tree in KathaUpanishad and in the Gita etc. They are all intended to make the student assimilate and see what the Upanishads reveal. But again, since nothing can really be compared to the final reality, no analogy is totally valid to convey what it is. The scope and limitations of these examples or analogies are clearly pointed out during the teaching.
Thus there is an evolved methodology of teaching embedded in the Upanishads themselves and transmitted by the tradition. It is technically called adhyaropa/apavada, superimposition/negation. By this methodology, the student is gradually taken from where he is, with his experiences and conclusions about the nature of himself and the world, to a point where he cannot but see the ultimate reality. This is achieved by leading him through successive steps (adhyaropa) that are just standpoints which are negated (apavada) for the student to understand the ultimate reality, called Brahman in Sanskrit.
Let us describe briefly some of the methods adopted by the Upanishads that all come under this general methodology of adhyaropa/apavada :