Pessoa.

To see the fields and the river

It isn't enough to open the window.

To see the trees and the flowers

It isn't enough not to be blind.

It is also necessary to have no philosophy.

With philosophy there are no trees, just ideas.

There is only each one of us, like a cave.

There is only a shut window, and the whole world outside,

And a dream of what could be seen if the window were opened, 

Which is never what is seen when the window is opened.

If poets merely dish out to the reader what they really feel in their day-to-day life, then they are giving too little.

(according to Fernando Pessoa)