Philosophical knowledge is the knowledge gained by reason from concepts ; mathematical knowledge is the knowledge gained by reason from the construction of concepts.
With regard to philosophical metaphysics, I always see increasing numbers who have attained to the negative goal, but as yet few who climb a few rungs backwards; one ought to look out, perhaps, over the last steps of the ladder, but not try to stand upon them.
And I entered and beheld with the eye of my soul... the Light Unchangeable... He that knows the Truth, knows what that Light is; and he that knows It, knows Eternity.