Chapter III – Advaita Prakarana (On Non-duality)
K 15-20 It is difficult to teach non-duality which is the final teaching of the Upanishad because the intellect is obsessed with worldly affairs which thrive on duality. There are three categories of students, the lowest, mediocre and the sharpest depending upon their maturity of intellect. A sharp intellect can understand that the world is like a dream, whereas Brahman alone is the reality. It is difficult for other two types of intellect. Therefore, the Upanishads introduce them to creation by using metaphors of clay-pot, gold-ornament, fire-spark, etc. As the teaching progresses, creation is negated by saying that effect is not different from the cause. Existence of the creation does not belong to it. The creation borrows it from Brahman which is the substratum and creation is superimposed upon It.