‘Without recourse to the conventional’ wrote Nāgārjuna [100 CE] ‘the ultimate cannot be shown’.
Nāgārjuna was a rightly celebrated Buddhist Scholar-Monk and his reference to the ‘Ultimate’ is par for the course. But what needs to be noted convincingly is that such terms as ‘Proximate and Ultimate’ are themselves very much conventional terms.
Immanuel Kant’s work which largely defined the domain of Academic Philosophy for 200 years had much to do with ‘Knowing’.
Kant tried to identify the ‘First Principles of Knowing’ itself, reaching back to Aristotle’s Principle of [Non] Contradiction and Categories [ Cause, Necessity, Contingency, etc ].
Along with ‘Space’ and ‘Time’, the ground conditions of Sensibility, they made up the Kantian Grid.
You cannot but view the World through these fundamental constructions, said Kant. They are organic contact lenses, hard-wired processors, the immutable framework within which must arise all Knowing and Understanding.
But what about these conditions themselves? How does one see one’s own organic contact lenses? How does one ‘Know the Knowing’?
Unlike most philosophers, Kant was vividly alert to the Self-Loop although he never took his own understanding of it to its necessary, implosive limit.
From Kant’s: ‘Critique of Pure Reason’:
‘If deduction of these conceptions is necessary, it must always be Transcendent. All attempts at an empirical deduction in regard to pure and a priori conceptions are in vain, and can only be done by one who does not understand the altogether peculiar nature of these conceptions.’
If you don’t see the significance of that qualification you will elaborate learnedly on the nature of Kant’s organic lenses while wearing them securely atop your nose.
And find yourself willy-nilly in the center of the vortex that is the Self-Loop. Which is exactly where Universities are today.
As always, all ‘First Principles’ including these, mount on a prior assumption of an ‘Independent and Separated ‘Self”. That does not take away from the depth of Kant’s insight.