If one indulges in intellectualism and perversity and lacks humility than it impossible to acquire Self-Knowledge or Brahma Gnana or Atma Gnana.

Consciousness is neither unknowable nor remains unknown at any moment. Only a Gnani can guide one to something which always remains unknown. If a Gnani can guide, it means that he knows what he says. Self-knowledge or Brahma Gnana   or Atma Gnana is quite easy to assimilate for those who are sincere, serious and receptive in their pursuit of truth.  If one indulges in intellectualism and perversity and lacks humility than it impossible to  acquire  Self-Knowledge or Brahma Gnana   or Atma Gnana.  Self-knowledge or Brahma Gnana   or Atma Gnana cannot be acquired if one always remains immersed in practical life within the practical world. 

"The fact that, the Vedas point to it only indirectly as 'not this - not this' shows that the knowledge can be imparted to others.

"Whatever it sees becomes known by the very soul or Consciousness the innermost self. One has to carefully analyze the underlying consciousness which is apart from universe yet illumines it the same. Know it to be the truth. What is not self-luminous can only fall within the orbit of witnessed and cannot be Formless witness itself. 

Formless witness is that by which three states are known; it cannot be what it is if it becomes the witnessed. What is formless witness (soul or consciousness) must always be different from witnessed (mind or universe or waking) itself, or else it could not be made known by it. Formless Witness (soul or consciousness) cannot admit of parts, which is the characteristic of witnessed (mind or universe or waking) Therefore objects take on shapes. One has to mentally eliminate witnessed (three states) from the   formless witness. 

"Just as a mirror takes on the hues of the images, so also the Consciousness assumes the different shapes of objects by virtue of its holding them within itself.

"Consciousness can thus be made manifest by eliminating from it all that can be known. It cannot be known as such and such, for it is the supporter of one and all. There is no other agent to neither know the Self nor light by which to know it.