"Truth is within ourselves;

 it takes no rise
From outward things,

 whate'er you may believe.
There is an inmost centre in us all,
Where truth abides in fulness;

 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 consists in opening out a way
Whence the imprisoned splendour may escape,
Than in effecting entry for a light
Supposed to be without."

Robert Browning