The following discussion is reproduced from the thread Mind Training" posted by Dan Hartwright on 3rd October 2003 at the Shaolin Wahnam Discussion Forum.
Non-thought is not thought or no-thought.
For example; I think of a book, this is thought, then I empty my mind, this is no-thought. Non-thought comes before the thought or no-thought process arises.
But, from another perspective, non-thought can both be thought or no-thought, and can occur during, before or after these processes.
Non-thought transcends dualistic thinking, whereas thought and no-thought are still dualistic.
Students at an Intensive Chi Kung Course in Malaysia enjoying a state of “non-thought” while performing Self-Manifested Chi Movement.
No-thought is still in the realm of attachment to phenomena, let go of 'that' and achieve non-thought.
As one famous Zen master said “You still have that!”
There is a detailed, but concise, explanation in the “Platform Sutra” by the 6th Patriarch Hui Neng, and there is also excellent commentary by Sifu in “The Complete Book of Shaolin.”
Non-thought is a crucial feature in Sitting Zen. It opens the meditator to cosmic wisdom, and at the highest level leads to enlightenment.
A fundamental point is not to intellectualize about these distinctions, because then you are at the thought level. Just let go of your thoughts, do not try and suppress them.
I am not sure if this will help or not but picture a calm pool of water with no disturbance, this is original mind. When a mental process arises, be this an active thought or the act of suppressing thought, then it is like dropping a stone into this pool.
The ripples caused by the stone are what we perceive as differentiated and separate phenomena, i.e. our phenomenal world. No-thought is still a thought process so is the same as a thought.
When we let go of the thought process then the pool is calm and flat and we see that ultimate reality is undifferentiated and encompasses all which we previously perceived as individual phenomena.
The 6th Patriarch would call this ?seeing your original mind/face'.
So, non-thought is important, and is a very important part of Zen, so stop thinking and start doing!