The true Self can never be known with the senses for it is unmanifest. It can only be known through the 'I" of your Being.
You are the "I" of Thy true Self - a Divine idea made manifest into an Instrument of Peace, so you both 'know' (Spiritual I) and are 'known'. (Minds I). Union of the two I's is Realization.
The I sees with 'Knowing' Aka Faith Aka claircognizance.
The eyeball can only know itself through 'Knowing' Aka Faith or claircognizance as it will never be able to see itself therefore never know itself through 'seeing' - through sensory perception.