We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time. Only… - T. S. Eliot

Only those who will risk going too far can possibly find out how far one can go.

A heap of broken images, where the sun beats,
And the dead tree gives no shelter, the cricket no relief,
And the dry stone no sound of water. Only
There is shadow under this red rock,
(Come in under the shadow of this red rock),
And I will show you something different from either
Your shadow at morning striding behind you
Or your shadow at evening rising to meet you;
I will show you fear in a handful of dust.

Someone said, 'The dead writers are remote from us because we know so much more than they did.' Precisely, and they are that which we know.

We do not pass through the same door twice
Or return to the door through which we did not pass