​Truth is within ourselves; it takes no rise
From outward things, what’er you may believe.
There is an inmost enter in us all,
Where truth abides in fullness; and around,
Wall upon wall, the gross flesh hems it in,
This perfect, clear perception—which is truth.
A baffling and perverting carnal mesh
binds it, and makes all error: and to know
Rather consist in opening out a way
whence the imprisoned splendor may escape,
than in effecting entry for a light
Supposed to be without.
— Robert Browning
from Paracelsus