Knowledge of material objects, the universe, mathematics, etc., implies getting information. The entire created world is in the category of the known, though one may know only parts of it and there may be many unknown areas yet to be known. Knowledge in the context of Vedanta is learning the truth of Self-knowledge and this is gained through an unlearning process, said Sri Rangan in a lecture.
In the thirteenth chapter of the Bhagavad Gita, Lord Krishna differentiates the objects to be known from the knower and this understanding is crucial to each one of us. The tendency to identify with the body, mind complex is very natural and strong. If for instance, a desk is recognised as a chair, it is a misunderstanding that gets cleared with proper guidance. But if an individual identifies himself with say, a chair, there is trouble in store. This is what happens when we identify ourselves with the attributes of the body, mind or intellect, when in reality each one's identity is the Self or Atma.
The powerful imprints from the outside world encourage such a misleading perception. We do see a subtle difference between our Self and the body when we call it “my body”, with a sense of possessiveness. Along with this is the sense of I (Ahamkara), when we take pride in our actions, thoughts, words, achievements, etc.
The truth is that the Self is a temporary resident in the body, which along with its attributes, functions, etc., is grouped under the term Kshetra, a field. The knower of this truth is called the Kshetrajna. The role an actor assumes is only for a brief spell of time against his own identity in life. Likewise, with individual life spans, the name and form endowed on the Self in every birth is for a longer spell, coming to an end with the death of the body, while the Self itself is immortal and exists beyond any span of Time.
The Self has to derecognise the mind, intellect and ego-sense as mere superimpositions on it because of its being associated with the body. But the body itself is a field through which the Self gets an opportunity to realise itself and the Supreme Brahman. This truth is mostly forgotten when the Self identifies with the body.