Whether you are going or staying
Sitting or lying down,
The whole world is your own self.
You must find out
Whether the mountains,
Rivers, grass, and forests 
Exist in your own mind
Or exist outside it.
Analyze the ten thousand things,
And when you take
This to the limit,
You will come to the limitless;
When you search into it,
You come to the end of search,
Where thinking goes no
Further and distinctions vanish.
When you smash the citadel of doubt,
Then the Buddha is simply yourself.

Lanxi Daolong (1213 CE-1278 CE), Lanxi Daolong was a famous Chinese Buddhist monk, calligrapher, idealist philosopher, and is the founder of the Kenchō-ji sect, which is a branch of the Rinzai school.